PLEXUS CORP, 424B3, 2000-09-21

PLEXUS CORP
424B3, 2000-09-21
PRINTED CIRCUIT BOARDS

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<PAGE> 1

THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED.
THIS PROSPECTUS IS NOT AN OFFER TO SELL SECURITIES, AND WE ARE NOT
SOLICITING OFFERS TO BUY THESE SECURITIES, IN ANY STATE WHERE THE OFFER OR
SALE IS NOT PERMITTED.

Rule 424B3
Reg. No. 333-45116

SUBJECT TO COMPLETION, DATED SEPTEMBER 21, 2000

[PLEXUS LOGO]

3,000,000 SHARES

COMMON STOCK

Plexus Corp. is offering 3,000,000 shares of common stock. Plexus
Corp.'s common stock is traded on the Nasdaq National Market under the symbol
"PLXS." The last reported sale price of the common stock on the Nasdaq National
Market on September 20, 2000 was $69.00 per share.

---------------------------

INVESTING IN OUR COMMON STOCK INVOLVES RISKS.
SEE "RISK FACTORS" BEGINNING ON PAGE 2 OF THE ACCOMPANYING PROSPECTUS.

---------------------------

<TABLE>
<CAPTION>
PER SHARE TOTAL
--------- -------
<S> <C> <C>
Public Offering Price....................................... $ $
Underwriting Discounts and Commissions...................... $ $
Proceeds to Plexus Corp. ................................... $ $
</TABLE>

THE SECURITIES AND EXCHANGE COMMISSION AND STATE SECURITIES REGULATORS
HAVE NOT APPROVED OR DISAPPROVED THESE SECURITIES, OR DETERMINED IF THIS
PROSPECTUS IS TRUTHFUL AND COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.

Plexus Corp. has granted the underwriters a 30-day option to purchase
up to an additional 450,000 shares of common stock to cover over-allotments.

---------------------------

ROBERTSON STEPHENS
SG COWEN
THOMAS WEISEL PARTNERS LLC
ROBERT W. BAIRD & CO.
THE DATE OF THIS PROSPECTUS SUPPLEMENT IS , 2000.
<PAGE> 2

YOU SHOULD RELY ONLY ON THE INFORMATION CONTAINED IN THIS PROSPECTUS. WE
HAVE NOT AUTHORIZED ANYONE TO PROVIDE YOU WITH INFORMATION DIFFERENT FROM THAT
CONTAINED IN THIS PROSPECTUS. WE ARE OFFERING TO SELL, AND SEEKING OFFERS TO
BUY, SHARES OF COMMON STOCK ONLY IN JURISDICTIONS WHERE OFFERS AND SALES ARE
PERMITTED.

------------------------

TABLE OF CONTENTS

<TABLE>
<CAPTION>
PAGE
----
<S> <C>
PROSPECTUS SUPPLEMENT
Summary..................................................... S-1
Use of Proceeds............................................. S-3
Price Range of Common Stock................................. S-3
Dividend Policy............................................. S-3
Capitalization.............................................. S-4
Selected Consolidated Financial Data........................ S-5
Management's Discussion and Analysis of Financial Condition
and Results of Operations................................. S-7
Business.................................................... S-12
Management.................................................. S-20
United States Federal Income Tax Consequences to Non-U.S.
Holders................................................... S-21
Underwriting................................................ S-24
Legal Matters............................................... S-27
Index to Consolidated Financial Statements.................. F-1
PROSPECTUS
About This Prospectus....................................... 1
The Company................................................. 1
Forward-Looking Statements and Cautionary Factors........... 1
Risk Factors................................................ 2
Where You Can Find More Information......................... 9
Use of Proceeds............................................. 11
Ratio of Earnings to Fixed Charges.......................... 11
Description of Debt Securities.............................. 11
Description of Capital Stock................................ 16
Book-Entry.................................................. 19
Plan of Distribution........................................ 21
Certain Legal Matters....................................... 22
Experts..................................................... 22
</TABLE>

------------------------

When used in this prospectus supplement, the terms "Plexus," "we," "our,"
"us" and the "Company" refer to Plexus Corp. and its subsidiaries. This
prospectus contains trademarks and trade names of other companies.

i
<PAGE> 3

SUMMARY

You should read the following summary together with the more detailed
information appearing elsewhere in this prospectus, including the documents
incorporated herein by reference.

OUR COMPANY

Plexus provides product realization services to original equipment
manufacturers, or OEMs, in the networking/telecommunications, medical,
industrial, computer and transportation industries. We provide advanced
electronics design, manufacturing and testing services to our customers and
focus on complex, high-end products. We offer our customers the ability to
outsource all stages of product realization, including: development and design,
materials procurement and management, prototyping and new product introduction,
testing, manufacturing and after-market support. For many customers, we serve
both a design and production function, allowing those customers to concentrate
on concept development, distribution and marketing, while accelerating their
time to market, reducing their investment in manufacturing capacity and
optimizing total product cost.

We believe that our broad service offerings with respect to the design and
realization of complex, high-end products within the electronics manufacturing
services, or EMS, industry provide us with significant competitive advantages.
Through a staff of over 350 product development engineers, we offer a complete
menu of engineering services, including digital and analog design, mechanical
and industrial design, embedded software design, printed circuit board design,
test equipment and software development, product verification and new product
introduction services. Our manufacturing services include printed circuit board
assembly, product configuration, testing, final product and system box build and
after-market support. Throughout the production process, we offer logistics
services, such as materials procurement, inventory management, packaging and
distribution.

OUR COMPETITIVE STRENGTHS

We believe we distinguish ourselves from our competitors by providing a
broad range of product realization services to electronics OEMs. We believe our
competitive advantages include our ability to:

- offer a complete menu of engineering services

- accelerate new product introduction and time to market for our customers

- provide a full range of product realization services, from product
development and design to new product introduction and manufacturing to
after-market support

- provide services for complex, high-end products.

OUR STRATEGY

Plexus' objective is to be the leading provider of product realization
services to the EMS industry, with a focus on high-end, value-driven engineering
and manufacturing services. We seek to provide our customers with a full range
of electronic product development, design, test and manufacturing services. Our
strategy for achieving this objective includes:

- leveraging our engineering expertise to generate profitable manufacturing
opportunities

- expanding our design and engineering expertise to increase the breadth of
services we provide

- utilizing our design, new product introduction, engineering and
manufacturing services to accelerate time to market for our customers

- using our design and engineering capabilities to focus on complex,
high-end products

- pursuing strategic acquisitions to expand our geographic reach and
service offerings.

S-1
<PAGE> 4

OUR ADDRESS

We were incorporated in Wisconsin in December 1979 as Plexus Corp. Our
principal executive offices are located at 55 Jewelers Park Drive, Neenah,
Wisconsin 54957-0156, and our telephone number at that location is (920)
722-3451.

THE OFFERING

Common stock offered by Plexus............ 3,000,000 shares

Common stock to be outstanding after the
offering.................................. 40,021,524 shares

Use of proceeds........................... We intend to use the estimated net
proceeds of $196.1 million:

- to repay, in part, existing
indebtedness

- to fund capital
expenditures, including
capacity expansion

- to finance, in part, the
cost of potential
acquisitions

- for general corporate
purposes, including working
capital.

See "Use of Proceeds."

Nasdaq National Market symbol............. PLXS

Unless otherwise indicated, the information in this prospectus supplement:

- assumes that the underwriters will not exercise their over-allotment
option to purchase up to 450,000 additional shares after the closing of
this offering

- gives effect to the two-for-one stock splits effective August 25, 1997
and August 31, 2000.

S-2
<PAGE> 5

USE OF PROCEEDS

We estimate that the net proceeds to us from the sale of the 3,000,000
shares of common stock offered hereby will be approximately $196.1 million,
based on an assumed offering price of $69.00 per share and after deducting the
underwriting discounts and commissions and estimated offering expenses. If the
underwriters' over-allotment option is exercised in full, we estimate that the
net proceeds will be approximately $225.5 million.

We intend to use the net proceeds from the sale of the shares of common
stock for one or more of the following purposes:

- repay, in part, existing indebtedness

- capital expenditures, including capacity expansion

- finance, in part, the cost of potential acquisitions

- general corporate purposes, including working capital.

We intend to use between $70.0 and $80.0 million of the net proceeds to
repay, in part, outstanding indebtedness under our revolving credit facility. As
of August 31, 2000, we had approximately $123.4 million of indebtedness
outstanding under our credit facility at a weighted average interest rate of 8.3
percent. The credit facility matures on June 15, 2003. Borrowings under the
credit facility in fiscal 2000 were used to fund acquisitions, for capacity
expansion and for general working capital purposes. The credit facility
currently provides for total availability of $130.0 million.

Pending the uses identified above, the net proceeds will be invested in
direct or guaranteed obligations of the U.S. government or other short-term
marketable securities.

PRICE RANGE OF COMMON STOCK

Our common stock is quoted on the Nasdaq National Market under the symbol
"PLXS." The following table sets forth, for the period indicated, the high and
low sale prices per share of our common stock on the Nasdaq National Market.

<TABLE>
<CAPTION>
PRICE RANGE OF
COMMON STOCK
------------------
HIGH LOW
------- -------
<S> <C> <C>
1999 FISCAL YEAR (ended September 30, 1999)
First Quarter............................................. $ 17.38 $ 8.50
Second Quarter............................................ $ 20.13 $ 12.81
Third Quarter............................................. $ 17.38 $ 13.38
Fourth Quarter............................................ $ 17.19 $ 13.94
2000 FISCAL YEAR (ending September 30, 2000)
First Quarter............................................. $ 24.50 $ 12.22
Second Quarter............................................ $ 37.00 $ 20.22
Third Quarter............................................. $ 57.63 $ 26.00
Fourth Quarter (through September 20, 2000)............... $ 81.00 $ 43.38
</TABLE>

On September 20, 2000, the last reported sale price of our common stock as
reported on the Nasdaq National Market was $69.00 per share.

DIVIDEND POLICY

We have never declared or paid any cash dividends on our common stock. We
anticipate that all earnings in the foreseeable future will be retained to
finance the development of our business.

S-3
<PAGE> 6

CAPITALIZATION

The following table sets forth our unaudited capitalization as of August
31, 2000:

- on an actual basis

- on an as adjusted basis to reflect the sale of 3,000,000 shares of
common stock offered hereby, at an assumed offering price of $69.00
per share, after deducting the underwriting discounts and commissions
and estimated offering expenses that we will pay, and the application
of the net proceeds of $196.1 million we will receive from the
offering in the manner described in "Use of Proceeds."

You should read this information together with our consolidated financial
statements and the related notes incorporated by reference into this prospectus,
"Management's Discussion and Analysis of Financial Condition and Results of
Operations," "Selected Consolidated Financial Data" and "Use of Proceeds."

<TABLE>
<CAPTION>
AUGUST 31, 2000
--------------------------------------
ACTUAL AS ADJUSTED
------ -----------
(IN THOUSANDS, EXCEPT PER SHARE DATA)
(UNAUDITED)
<S> <C> <C>
Cash and cash equivalents................................... $ 2,710 $125,360
======== ========
Credit facility, including current portion.................. $123,400 $ 50,000
Other long-term debt........................................ 10,796 10,796
-------- --------
Total debt........................................... 134,196 60,796
-------- --------
Stockholders' equity:
Preferred stock, $0.01 par value; authorized shares--5,000;
issued and outstanding shares--none....................... -- --
Common stock, $0.01 par value; authorized shares--60,000;
issued and outstanding shares--37,022 actual and 40,022 as
adjusted.................................................. 370 400
Additional paid-in capital.................................. 72,912 268,932
Accumulated other comprehensive income...................... (383) (383)
Retained earnings........................................... 128,793 128,793
-------- --------
Total stockholders' equity........................... 201,692 397,742
-------- --------
Total capitalization................................. $335,888 $458,538
======== ========
</TABLE>

S-4
<PAGE> 7

SELECTED CONSOLIDATED FINANCIAL DATA

The following selected consolidated financial data should be read in
conjunction with our consolidated financial statements and related notes
included and incorporated by reference herein. The consolidated financial
statements have been prepared to give retroactive effect to the merger with
SeaMED Corporation on July 23, 1999, which was accounted for as a pooling of
interests. The selected consolidated financial data as of and for each of the
years in the five-year period ended September 30, 1999 have been derived from
our consolidated financial statements. The unaudited consolidated financial data
for the nine months ended June 30, 1999 and 2000 have been derived from our
financial records.

<TABLE>
<CAPTION>
NINE MONTHS
FISCAL YEAR ENDED SEPTEMBER 30, ENDED JUNE 30,
---------------------------------------------------- -----------------------
1995 1996 1997 1998 1999 1999 2000
-------- -------- -------- -------- -------- -------- --------
(unaudited)
(in thousands, except per share data)
<S> <C> <C> <C> <C> <C> <C> <C>
OPERATING STATEMENT DATA:
Net sales.............................. $300,795 $342,254 $438,565 $466,795 $492,414 $360,180 $502,275
Cost of sales.......................... 274,207 311,094 387,333 406,648 426,005 312,734 430,604
-------- -------- -------- -------- -------- -------- --------
Gross profit........................... 26,588 31,160 51,232 60,147 66,409(1) 47,446(2) 71,671
-------- -------- -------- -------- -------- -------- --------
Operating expenses:
Selling and administrative........... 13,081 15,546 20,463 23,754 26,443 19,863 24,487
Plant closing, relocation and
severance.......................... -- -- -- -- 981 765 --
Merger/acquisition costs............. -- -- -- -- 4,557 -- 1,062
Amortization of goodwill............. -- -- -- -- -- -- 222
-------- -------- -------- -------- -------- -------- --------
Total operating expenses........... 13,081 15,546 20,463 23,754 31,981 20,628 25,771
-------- -------- -------- -------- -------- -------- --------
Operating income....................... 13,507 15,614 30,769 36,393 34,428(1) 26,818(2) 45,900(3)
Other income (expense):
Interest expense..................... (2,664) (2,286) (1,014) (86) (274) (253) (435)
Miscellaneous........................ 325 464 1,160 975 1,995 1,680 1,388
-------- -------- -------- -------- -------- -------- --------
Income before income taxes............. 11,168 13,792 30,915 37,282 36,149 28,245 46,853
Income taxes........................... 4,095 5,442 12,022 14,345 15,838 11,430 18,830
-------- -------- -------- -------- -------- -------- --------
Net income............................. $ 7,073 $ 8,350 $ 18,893 $ 22,937 $ 20,311(1) $ 16,815(2) $ 28,023(3)
======== ======== ======== ======== ======== ======== ========
Earnings per share:
Basic................................ $ 0.24 $ 0.29 $ 0.60 $ 0.68 $ 0.59 $ 0.49 $ 0.78
Diluted.............................. $ 0.22 $ 0.26 $ 0.54 $ 0.63 $ 0.55(1) $ 0.45(2) $ 0.73(3)
Weighted average shares outstanding:
Basic................................ 26,280 26,472 30,732 33,688 34,646 34,528 35,740
Diluted.............................. 31,436 31,850 35,116 36,196 37,021 36,984 38,324
BALANCE SHEET DATA:
Working capital........................ $ 75,374 $ 55,683 $ 70,544 $ 91,159 $110,411 $113,927 $146,154
Total assets........................... 124,345 122,301 152,453 184,354 229,636 218,812 393,254
Long-term debt......................... 42,955 16,658 3,516 2,587 142 2,814 46,893
Stockholders' equity................... 45,826 53,788 89,404 115,863 146,403 141,522 187,707
OTHER DATA:
EBITDA(4).............................. $ 17,165 $ 19,961 $ 36,330 $ 44,765 $ 52,136 $ 36,913 $ 57,592
Return on average assets............... 5.6% 6.8% 13.8% 13.6% 9.8% 11.1%(5) 12.0%(5)
Return on average equity............... 17.0% 16.8% 26.4% 22.3% 15.5% 17.4%(5) 22.4%(5)
Inventory turnover ratio(6)............ 4.8x 5.6x 6.6x 7.1x 6.2x 6.9x 4.6x
</TABLE>

S-5
<PAGE> 8

------------

(1) In connection with the acquisition of SeaMED Corporation, we recorded merger
and other one-time related charges in fiscal 1999 of approximately $7.7
million (approximately $6.0 million after-tax). Excluding these charges,
gross profit would have been approximately $68.6 million, operating income
would have been approximately $42.1 million, net income would have been
approximately $26.3 million and diluted earnings per share would have been
$0.71.

(2) In connection with the operations of SeaMED Corporation, we recorded
one-time charges in the nine months ended June 30, 1999 of approximately
$2.9 million (approximately $1.9 million after tax) relating to plant
closing costs, the write down of obsolete inventory and a loss on an
engineering contract. Excluding these charges, gross profit would have been
approximately $49.6 million, operating income would have been approximately
$29.8 million, net income would have been approximately $18.8 million and
diluted earnings per share would have been $0.51.

(3) In connection with the acquisition of Agility, Incorporated and the
acquisition of the turnkey electronics manufacturing services operations of
Elamex, S.A. de C.V., we recorded one-time acquisition-related charges in
the nine months ended June 30, 2000 of approximately $1.1 million
(approximately $0.7 million after tax). Excluding these one-time charges,
operating income would have been approximately $47.0 million, net income
would have been approximately $28.8 million and diluted earnings per share
would have been $0.75.

(4) "EBITDA" is defined as operating income before depreciation, amortization
and one-time charges. EBITDA does not represent and should not be considered
as an alternative to net income or cash flow from operations as determined
by generally accepted accounting principles. Our EBITDA calculation may not
be comparable to that reported by other companies. EBITDA does not take into
account our working capital, debt service and capital expenditure
requirements and other commitments and, accordingly, is not necessarily
indicative of amounts that may be available for discretionary use.

(5) Calculations for the nine months ended June 30, 1999 and 2000 are
annualized.

(6) Calculations of inventory turnover are based on average inventory turnover
for the period and are annualized for the nine months ended June 30, 1999
and 2000. Our quarterly calculations of inventory turnover, which are
included and incorporated by reference herein, are based on inventory at
period end.

S-6
<PAGE> 9

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
AND RESULTS OF OPERATIONS

OVERVIEW

Plexus provides product realization services to original equipment
manufacturers, or OEMs, in the networking/telecommunications, medical,
industrial, computer and transportation industries. We provide advanced
electronics design, manufacturing and testing services to our customers and
focus on complex, high-end products. We offer our customers the ability to
outsource all stages of product realization, including: development and design,
materials procurement and management, prototyping and new product introduction,
testing, manufacturing and after-market support. The following information
should be read in conjunction with our consolidated financial statements
included and incorporated by reference herein and the "Risk Factors" section
beginning on page 2 of the accompanying prospectus.

We provide contract manufacturing services on either a turnkey basis, where
we procure some or all of the materials required for product assembly, or on a
consignment basis, where the customer supplies some, or occasionally all,
materials necessary for product assembly. Turnkey services include materials
procurement and warehousing in addition to manufacturing and involve greater
resource investment and inventory risk management than consignment services.
Turnkey manufacturing currently represents almost all of our net sales. Turnkey
sales typically generate higher sales and higher gross profit dollars with lower
gross margin percentages than consignment sales due to the inclusion of
component costs, and related markup, in our net sales. However, turnkey
manufacturing involves the risk of inventory management, and a change in
component costs can directly impact average selling prices, gross margins and
our net sales. Due to the nature of turnkey manufacturing, our quarterly and
annual results are affected by the level and timing of customer orders,
fluctuations in materials costs and the degree of automation used in the
assembly process.

On April 28, 2000, we acquired Agility, Incorporated, a privately-held,
Boston-based EMS provider. The transaction was accounted for as a pooling of
interests. However, our prior results were not restated, as they would not
differ materially from reported results. Agility's results are included only for
the third fiscal quarter of 2000. The addition of Agility establishes a stronger
presence with our current East coast customers and increases our capacity to
assemble complex printed circuit boards with complete final product and system
box build.

On May 23, 2000, we completed our acquisition of the turnkey electronics
manufacturing services operations of Elamex, S.A. de C.V., located in Juarez,
Mexico. We refer to these operations as the Mexico turnkey operations. We
accounted for this acquisition using the purchase method of accounting, and the
Mexico turnkey operations' results are included in our results from the date of
acquisition. We anticipate that the Mexico turnkey operations will provide our
existing and potential customers with a proven low-cost-labor solution for many
of our product realization services. In addition, the acquisition provides the
existing customers of the Mexico turnkey operations with access to our
engineering, test and technology capabilities.

On July 14, 2000, we completed our acquisition of Keltek (Holdings)
Limited. We accounted for the Keltek acquisition using the purchase method of
accounting. As a result, the effects of the acquisition will be reflected in our
financial statements from and subsequent to the date of acquisition. This
acquisition provided us with our first engineering and assembly facilities
outside North America. The acquired operations are headquartered in Kelso,
Scotland, with an additional facility in Maldon, England. The addition of Keltek
provides us with a presence in Europe to service both current and new customers.

RESULTS OF OPERATIONS

Results have been restated to reflect our fiscal 1999 merger with SeaMED in
a transaction accounted for as a pooling of interests.

S-7
<PAGE> 10

NINE MONTHS ENDED JUNE 30, 2000 COMPARED TO NINE MONTHS ENDED JUNE 30, 1999

Net sales. Net sales for the nine months ended June 30, 2000 increased 39
percent to $502 million from $360 million for the nine months ended June 30,
1999. This increase was due primarily to steady growth in the
networking/telecommunications and medical sectors from both existing and new
customers obtained through internal growth and through our acquisitions. Our
acquisitions during fiscal 2000 accounted for slightly more than 8 percent of
net sales for the nine months ended June 30, 2000. The growth in the
networking/telecommunications and medical industries was offset somewhat by a
reduction in sales to the computer and transportation industry and reduced sales
volumes at our SeaMED operations. We believe that our overall sales growth
reflects the continuing trend toward outsourcing within the electronics
industry.

Our largest customers for the nine months ended June 30, 2000, were Lucent
Technologies and General Electric, which accounted for 24 percent and 11 percent
of net sales, respectively, compared to the nine months ended June 30, 1999 when
Lucent Technologies and General Electric accounted for 16 percent and 12 percent
of net sales, respectively. No other customers accounted for more than 10
percent of our net sales for the nine months ended June 30, 2000 or 1999. Sales
to our ten largest customers accounted for 67 percent of net sales for the nine
months ended June 30, 2000, compared to 64 percent for the same period in fiscal
1999. As with sales to most of our customers, sales to our largest customers may
vary from time to time depending on the size and timing of customer program
commencement, termination, delays, modifications and transitions. For example,
in reviewing anticipated future program changes over the next six to nine months
for Lucent Technologies, we believe that sales to Lucent Technologies may
decrease somewhat, even though Lucent Technologies should remain a significant
customer and represent more than 10 percent of our net sales. In addition, based
on customer forecasted demand, we currently anticipate that Cisco Systems will
become our largest customer for fiscal 2001 and represent up to approximately 20
percent of our net sales. We remain dependent on continued sales to Lucent
Technologies, General Electric, Cisco Systems and our other significant
customers, and we generally do not obtain firm, long-term purchase commitments
from our customers. Although any material change in orders from these or other
customers could materially affect our results of operations, we are dedicated to
diversifying our customer base and decreasing our dependence on any particular
customer or customers.

Our net sales for the nine months ended June 30, 2000 and 1999,
respectively, by industry were as follows: networking/telecommunications 35
percent (24 percent), medical 29 percent (31 percent), industrial 19 percent (22
percent), computer 10 percent (14 percent) and transportation/other 7 percent (9
percent). We expect the percentage of net sales to the
networking/telecommunications industry to continue to grow in the fourth quarter
of fiscal 2000 and fiscal 2001.

Gross profit. Gross profit for the nine months ended June 30, 2000
increased 51 percent to $71.7 million from $47.4 million for the nine months
ended June 30, 1999. The gross margin for the nine months ended June 30, 2000
was 14.3 percent, compared to 13.2 percent for the nine months ended June 30,
1999. The gross margin increase was due primarily to the inclusion of $2.2
million of one-time SeaMED merger-related charges from the write down of
obsolete inventory and a loss on an engineering contract for the nine months
ended June 30, 1999.

Most of the research and development we conduct is paid for by our
customers and is, therefore, included in the cost of sales. We conduct other
research and development, but that research and development is not specifically
identified, as we believe such expenses are less than one percent of our net
sales.

Our gross margin reflects a number of factors that can vary from period to
period, including product mix, the level of start-up costs and efficiencies of
new programs, product life cycles, sales volumes, price erosion within the
electronics industry, capacity utilization of surface mount and other equipment,
labor costs and efficiencies, the management of inventories, component pricing
and shortages, average sales prices, the mix of turnkey and consignment
business, fluctuations and timing of customer orders, changing demand for
customers' products and competition within the electronics industry. Overall
gross margins continue to be affected by SeaMED's reduced sales volume, the
effect of which may continue until

S-8
<PAGE> 11

synergies and efficiencies are realized and SeaMED's cost structure is aligned
with its reduced sales volume, or until sales volumes increase. In addition, we
expect gross margins resulting from the Mexico turnkey and Keltek operations to
be below our historical gross margins. These and other factors can cause
variations in our operating results. Although our focus is on maintaining and
expanding gross margins, there can be no assurance that gross margins will not
decrease in future periods. Gross margins are expected to decrease in the
near-term due to our recent acquisitions.

Operating expenses. Selling and administrative (S&A) expenses for the nine
months ended June 30, 2000 increased 23 percent to $24.5 million from $19.9
million for the nine months ended June 30, 1999. As a percentage of net sales,
S&A expenses were 4.9 percent for the nine months ended June 30, 2000 compared
to 5.5 percent for the nine months ended June 30, 1999. The increase was due
primarily to increases in our sales and marketing efforts and information
systems support, while the decrease as a percentage of net sales was
attributable to efficiencies associated with additional sales. We anticipate
that future S&A expenses will increase in absolute dollars, but will remain
approximately 5 percent of net sales, as we continue to expand these support
areas.

Acquisition costs of approximately $1.1 million for the nine months ended
June 30, 2000 related to costs associated with the Agility and Mexico turnkey
operations acquisitions. Plant closing, relocation and severance costs of
approximately $0.8 million for the nine months ended June 30, 1999 were incurred
by a SeaMED subsidiary prior to our merger with SeaMED.

Income taxes. Income taxes increased to $18.8 million for the nine months
ended June 30, 2000, from $11.4 million for the nine months ended June 30, 1999,
as a result of increased earnings. Our effective income tax rate has remained at
approximately 40 percent. This rate approximates the blended federal and state
statutory rate. The effective tax rate increased slightly upon the completion of
the Mexico turnkey operations acquisition arising from the tax treatment of
goodwill and is expected to increase again in the fourth quarter of 2000. The
overall impact of these increases in our effective tax rate is not expected to
be material to our net income. In fiscal 2001, we expect the effective tax rate
to decrease as foreign operations increase.

FISCAL 1999 COMPARED TO FISCAL 1998

Net sales. Net sales for fiscal 1999 increased 5 percent to $492 million
from $467 million for fiscal 1998. For fiscal 1999, unit volume sales were
strong; however, sales growth was impacted by industry-wide pressure on average
selling prices, component prices and our continued focus to move toward higher
technology businesses. In addition, in fiscal 1999, net sales by SeaMED
decreased approximately $8 million from fiscal 1998 levels.

The principal change in our net sales mix for fiscal 1999 compared to
fiscal 1998 was in the networking/telecommunications industry, which increased
from 15 percent to 24 percent of our net sales. This increase was offset by a
decline in the computer industry to 14 percent from 23 percent of our net sales.
The increase in sales to the networking/telecommunications industry was
primarily a result of increased sales to Lucent Technologies in fiscal 1999. Net
sales for fiscal 1999 for the other industries we served were as follows:
medical 31 percent (29 percent in fiscal 1998), industrial 23 percent (20
percent in fiscal 1998), transportation/other 8 percent (13 percent in fiscal
1998).

Our largest customers for fiscal 1999 were Lucent Technologies, which
accounted for 16 percent of net sales, and General Electric, which accounted for
12 percent of net sales. No customer accounted for more than 10 percent of our
fiscal 1998 net sales. Sales to our ten largest customers accounted for 61
percent of net sales for both fiscal 1999 and 1998.

Gross profit. Gross profit for fiscal 1999 increased 10 percent to $66.4
million from $60.1 million for fiscal 1998. The gross margin for fiscal 1999 was
13.5 percent, compared to 12.9 percent for fiscal 1998. Excluding the one-time
SeaMED merger-related charges of $2.2 million related to the write down of
obsolete inventory and a loss on an engineering contract, the fiscal 1999 gross
profit and margin would have been $68.6 million and 13.9 percent, respectively.
The continued improvement in gross margin for fiscal 1999 compared to fiscal
1998 reflected our focus on business mix and continued operating

S-9
<PAGE> 12

efficiencies, which were partially offset by increased costs for expansion of
engineering and technical manufacturing capabilities to meet customer demands.

Operating expenses. S&A expenses for fiscal 1999 increased 11 percent to
$26.4 million from $23.8 million for fiscal 1998. As a percentage of net sales,
S&A expenses were 5.4 percent for fiscal 1999 compared to 5.1 percent for fiscal
1998. The increase in S&A expenses was primarily attributable to increased
engineering, sales and marketing, and information systems support. In fiscal
1999, we also had one-time merger costs of $4.6 million and other one-time
merger-related charges (primarily for plant closings, relocation and severance)
of $1.0 million associated with our acquisition of SeaMED.

Income taxes. Income taxes increased to $15.8 million for fiscal 1999 from
$14.3 million for fiscal 1998, as a result of increased earnings. Our effective
income tax rate for fiscal 1999 increased as a result of non-tax deductible
merger expenses. Excluding these one-time expenses, the effective tax rate
remained relatively constant at rates between 38 percent to 40 percent for
fiscal 1999 and 1998. These rates approximate the blended federal and state
statutory rate.

FISCAL 1998 COMPARED TO FISCAL 1997

Net sales. Net sales for fiscal 1998 increased 6 percent to $467 million
from $439 million for fiscal 1997. Net sales for fiscal 1998 increased due to
the addition of new programs and new customers, primarily Lucent Technologies.
This increase was offset by several factors including: (1) the decision by some
customers to transition manufacturing to their own in-house manufacturing
facilities, primarily Motorola; (2) our decision to exit certain automotive and
other commodity-oriented markets, primarily computer peripherals, whose
businesses are no longer compatible with our long-term growth plans; (3)
decreasing component pricing with related decreases in average selling prices;
(4) a general weakening of certain markets, primarily industrial semiconductors,
in which we operate; and (5) the negative effects of the strong U.S. dollar and
the Southeast Asian market's unfavorable economic conditions and the impact of
such on a few of our customers.

In fiscal 1998, no customers accounted for more than 10 percent of our net
sales. In fiscal 1997, General Electric and International Business Machines
Corporation accounted for 11 percent and 10 percent of net sales, respectively.
Sales to our ten largest customers accounted for 61 percent of net sales for
both fiscal 1998 and 1997.

Gross profit. Gross profit for fiscal 1998 increased 17 percent to $60.1
million from $51.2 million for fiscal 1997. The gross margin for fiscal 1998 was
12.9 percent, compared to 11.7 percent for fiscal 1997. The continued
improvement reflected our focus on business mix and continued operating
efficiencies, which were partially offset by increased costs for expansion of
engineering and technical manufacturing capacity to meet customer demands.

Operating expenses. S&A expenses for fiscal 1998 increased 16 percent to
$23.8 million from $20.5 million for fiscal 1997. As a percentage of net sales,
S&A expenses were 5.1 percent for fiscal 1998 compared to 4.7 percent for fiscal
1997. The increase in S&A expenses was primarily attributable to increased
engineering, sales and marketing and information systems support.

Income taxes. Income taxes increased to $14.3 million for fiscal 1998 from
$12.0 million for fiscal 1997, as a result of increased earnings. The effective
tax rate remained relatively constant at rates between 38 percent to 40 percent
for fiscal 1998 and 1997. These rates approximate the blended federal and state
statutory rate.

LIQUIDITY AND CAPITAL RESOURCES

Cash flows used in operating activities were $8.0 million for the nine
months ended June 30, 2000, compared to cash flows provided by operating
activities of $22.0 million in the comparable period in fiscal 1999. During the
first nine months of fiscal 2000, cash used in operating activities primarily
related to increases in accounts receivable and inventories to support increased
sales offset in part by increases in net income, accounts payable and accrued
liabilities. The increase in our inventory levels was due to our decision to

S-10
<PAGE> 13

support anticipated future sales growth, and to maintain higher levels of
components going forward in view of the tightening of certain component markets.
The increase also reflected lower inventory turns at our new Mexico turnkey
operations. As a result, annualized inventory turnover decreased to 4.6 turns
for the nine months ended June 30, 2000 from 6.9 turns for the nine months ended
June 30, 1999 and from 6.2 turns for all of fiscal 1999. Due to the increase in
sales for the nine months ended June 30, 2000, accounts receivable and accounts
payable increased significantly.

Cash flows used in investing activities totaled $64.9 million for the nine
months ended June 30, 2000, primarily for acquisition of the Mexico turnkey
operations, purchases of short-term investments and payments for additional
property, plant and equipment, partially offset by the maturity of short-term
investments. In connection with our July 2000 acquisition of the net assets of
Keltek, we used approximately $19.1 million in cash, incurred approximately $2.7
million of additional liabilities and issued approximately $7.1 million in
notes.

We utilize available cash, debt and operating leases to fund our operating
requirements. We utilize operating leases primarily in situations where
technical obsolescence concerns are determined to outweigh the benefits of
financing the equipment purchase. We estimate capital expenditures for fiscal
2000 will be approximately $50 million, including the expansion of our Neenah,
Wisconsin engineering facility currently in progress, the purchase of an
existing manufacturing facility in Appleton, Wisconsin and the purchase of
additional equipment for existing locations. We currently expect fiscal 2001
capital expenditures will increase to approximately $75 million to support
anticipated sales growth. This includes planned expansions at our manufacturing
facilities in Kentucky and Illinois and additional manufacturing equipment.

Cash flows provided by financing activities totaled $62.7 million for the
nine months ended June 30, 2000, primarily representing borrowings under our
credit facility and proceeds from the exercise of stock options (including
related tax benefits), partially offset by payments on debt. The ratio of total
debt to equity was 1.1 to 1 and 0.6 to 1 as of June 30, 2000 and September 30,
1999, respectively.

On June 15, 2000, we entered into an amended and restated credit agreement,
which provided us with a $100.0 million credit facility, and subsequently
entered into an amendment that increased total availability under the credit
facility to $130.0 million. On August 31, 2000, we had borrowed approximately
$123.4 million under our credit facility and had approximately $10.8 million of
other borrowings, principally consisting of approximately $7.1 million of notes
issued in connection with the Keltek acquisition. On September 15, 2000, we
entered into a short-term demand note with one of the lenders under our credit
facility that provides us with an additional $60.0 million of financing
availability. This short-term demand note matures on November 30, 2000. We
anticipate pursuing an amendment to our credit facility to replace the demand
note and to increase total availability to $200.0 million to provide additional
financing capacity to fund anticipated working capital needs to support growth
and expansion of our manufacturing facilities and for potential additional
acquisitions. The lenders under the credit facility are under no obligation to
increase our borrowing capacity and we cannot assure you that we will be able to
expand the capacity to the extent desired, if at all, or on commercially
reasonable terms. In addition, our ability to secure any amendment to the credit
facility depends in part on our continued compliance with applicable operating
covenants. Our credit facilities, leasing capabilities, the proceeds of this
offering, cash and short-term investments and projected cash from operations
should be sufficient to meet our working capital and capital requirements
through fiscal 2000 and the foreseeable future.

Although there can be no assurance that future financing will be available
on terms acceptable to us, we may seek to raise additional capital through the
issuance of either public or private debt or equity securities to finance future
acquisitions. Debt financings may require us to pledge assets as collateral.
Equity financing may result in dilution to shareholders. Failure to arrange
additional financing on commercially reasonable terms could affect our ability
to expand our operations.

We have not paid dividends on our common stock, but have reinvested our
earnings to support our working capital and expansion requirements. We intend to
continue to utilize our earnings in the development of our business and do not
expect to pay cash dividends in the foreseeable future.

S-11
<PAGE> 14

BUSINESS

OVERVIEW

We believe that our broad service offerings with respect to the design and
realization of complex, high-end products within the electronics manufacturing
services, or EMS, industry provide us with a significant competitive advantage.
Through a staff of over 350 product development engineers, we offer a complete
menu of engineering services, including digital and analog design, mechanical
and industrial design, embedded software design, printed circuit board design,
test equipment and software development, product verification and new product
introduction services. Our manufacturing services include printed circuit board
assembly, product configuration, testing, final product and system box build and
after-market support. Throughout the production process, we offer logistics
services, such as materials procurement, inventory management, packaging and
distribution.

Our customers include industry leading OEMs such as Lucent Technologies,
Cisco Systems, General Electric, Unisys, Siemens, Honeywell and Johnson &
Johnson, and emerging technology companies such as Equipe Communications, Gotham
Networks and Sitara Networks. Due to our focus on serving OEMs in high-growth
technology and medical sectors, our business is influenced by major
technological trends such as the level and rate of development of fiber optics
infrastructure, the expansion of network computing and Internet use, and the
expansion of outsourcing by OEMs generally.

Established in 1979, we have approximately 5,300 full-time employees and 18
facilities in 13 locations totaling approximately 1.25 million square feet. Over
the past year, we have expanded our capacity and geographic reach through a
series of strategic acquisitions. Through these transactions, we have enhanced
our access to and ability to provide services within important technology
corridors in Boston, Chicago and Seattle; established a base in Europe;
significantly increased the size and capabilities of our medical services
offerings; significantly expanded our capacity with respect to the assembly of
configured-to-order wireless products; and acquired proven low-cost
manufacturing operations in Mexico.

INDUSTRY BACKGROUND

The EMS industry is comprised of companies that provide a range of
manufacturing services to electronics OEMs. The EMS industry has experienced
rapid growth in recent years, due to the expansion of the overall industry and
increased outsourcing of manufacturing and related functions by electronics
OEMs. These growth characteristics are driven by accelerating product
development cycles, the demand for network infrastructure expansion to handle
greater voice and data traffic and the enhanced functionality of communications
devices. Technology Forecasters projects that the EMS industry will grow by
approximately 28 percent each year through 2004, with total industry sales
projected to be approximately $260.3 billion by 2004.

S-12
<PAGE> 15

HISTORICAL AND PROJECTED EMS INDUSTRY REVENUE GROWTH

[ANNUAL GROWTH RATE TABLE]

<TABLE>
<CAPTION>
28% 5 YEAR COMPOUNDED ANNUAL GROWTH RATE
----------------------------------------
<S> <C>
1998 60.0
1999 78.0
2000 100.9
2001 129.9
2002 164.6
2003 207.0
2004 260.3
</TABLE>

<TABLE>
<S> <C> <C> <C> <C> <C> <C> <C>
Percent Outsourced 9.5% 11.2% 13.1% 15.6% 18.4% 21.8% 25.9%
</TABLE>

Source: Technology Forecasters, Inc. report
dated August 2000

OEMs have increasingly outsourced manufacturing and other related functions
to EMS companies in an effort to focus their own resources on core competencies,
while leveraging the expertise of EMS providers in design, procurement, assembly
and test operations and supply chain management. Technology Forecasters
estimates that the percentage of total cost of goods sold in the electronics
industry which is outsourced for manufacture by OEMs will increase from 9.5
percent in 1998 to 25.9 percent by 2004.

As OEM outsourcing has increased, many EMS providers have established
strong strategic relationships with their OEM customers. In addition, some OEMs
have sold manufacturing operations to EMS providers with demonstrated expertise
in generating manufacturing efficiencies. Key benefits to OEMs from outsourcing
include:

- accelerated time to market and decreased time-to-volume manufacturing

- reduced operating costs and capital requirements

- increased ability to focus resources on core competencies

- improved access to leading design and manufacturing technologies

- increased ability to leverage EMS companies' logistics expertise

- improved inventory management and purchasing power.

COMPETITIVE ADVANTAGES

We believe that we distinguish ourselves from our competitors by providing
a wide range of product realization services to electronics OEMs. Our
competitive advantages include our ability to:

Offer a complete menu of engineering capabilities. With over 20 years of
experience in electronics design engineering, we provide comprehensive
engineering and design services, including printed circuit board design,
hardware and software design, test design, prototyping and new product
introduction. For example, we are a leading provider of these design and
engineering services to the medical products manufacturing industry. Our
engineering capability is a core strength, and we currently maintain a staff of
over 350 product development engineers. Our engineers possess hard-to-find
skills such as application-specific integrated circuit design, radio frequency
design, power supply design, optical network design and embedded software
engineering.

Accelerate new product introduction and time to market for our
customers. Because we offer a full range of electronic product development and
design and test engineering services, we are able to accelerate the time to
market for our customers' products. Through our New Product Introduction Plus
centers, we offer our customers concurrent product and test design services,
prompt turnaround of prototyping and

S-13
<PAGE> 16

testing solutions and pilot production product runs, with the goal of providing
a smooth, cost-effective transition to volume production and accelerating time
to market for our customers' products.

Provide a full range of product realization services. Along with our
engineering and design capability, we offer manufacturing and assembly services.
We have the expertise to assemble very complex electronic products that utilize
multiple printed circuit boards and subassemblies. We are particularly
experienced in the networking/telecommunication and medical industries. We also
offer assembly services such as configuring products and incorporating
electronic assemblies into subassemblies and fabricating products from
components manufactured to specification by others. We believe that by offering
a full range of product realization services, we reduce our customers' costs and
accelerate the time to market for their products.

Provide services for complex, high-end products. Because of our engineering
expertise and high-end manufacturing capabilities, we focus on providing
services for complex products such as optical switches, radio frequency/wireless
technology, ultrasound devices and other complex medical device products. As a
result, we are able to attract customers in high-end, emerging technology
markets such as optical networking, radio frequency and wireless technology.

STRATEGY

Plexus' objective is to be the leading provider of product realization
services in the EMS industry, with a focus on high-end, value-driven engineering
and manufacturing services. We seek to provide our customers with a full range
of electronic product development and design, new product introduction, test and
manufacturing services. Our strategy includes:

Leveraging our engineering expertise. We intend to continue to leverage our
engineering and design leadership to generate profitable manufacturing
opportunities. For example, our printed circuit board design and test
development services have led to new contracts in the medical and
networking/telecommunications industries, including optical networking programs.
Leveraging our engineering expertise also allows us to cultivate an engineering
sales channel and enables us to more effectively survey the marketplace of
emerging products and technologies for potential new customers and products.

Expanding our design engineering expertise. We intend to continue expanding
our engineering and design expertise and the breadth of engineering and design
services we provide. We actively recruit new engineering talent and focus on
retaining our existing engineering staff. In addition, a primary focus of our
acquisition strategy is to increase our engineering capabilities and capacity.
We also seek to enter into strategic alliances with research and development
organizations that enable us to provide complementary technologies and broader
services to our customers. We will strive to use our expanding engineering and
design capability base to provide more expertise and a broader range of customer
services.

Accelerating time to market for our customers. Our design engineering,
testing and new product introduction services help our customers reduce the time
to market for their products. Our New Product Introduction Plus centers provide
quick turnaround of prototyping and printed circuit board design and provide
timely and cost-effective testing solutions, which helps speed the transition to
volume production. Our ability to reduce customers' time to market allows us to
attract new customers and to pursue opportunities to provide services for new
products, including those in emerging technology markets.

Focusing on complex, high-end products. We intend to continue using our
engineering and design capabilities to focus on complex, high-end products. We
will continue to explore new opportunities to provide services focused on
high-end products through our expanded presence in important technology
corridors, our strategic alliances with research and development organizations
and our engineering and design expertise.

Pursuing strategic acquisitions to expand our geographic reach and service
offerings. We continue to review opportunities to acquire engineering and
manufacturing operations in North America, Europe and Asia. Expanding our
geographic reach broadens the services we offer and enhances our customer
relationships. The primary focus of these geographic and service expansions is
to enable our customers to focus on their core competencies and reduce
development cost and time to market for their products.

S-14
<PAGE> 17

SERVICES

Plexus offers a broad range of integrated services that provide customers
with a total design, new product introduction and manufacturing solution to take
a product from initial design through production to after-market support. Our
customers may utilize any or all of the following services and tend to use more
of these services as their outsourcing strategies mature:

Product development and design. We provide comprehensive product
development and design and test engineering services. These services include
project management, initial feasibility studies, product concept definition,
specifications for product features and functions, product engineering
specifications, microprocessor selection, circuit design, software design,
application-specific integrated circuit design, printed circuit board layout,
product housing design, development of test specifications and product
validation testing. Through our product development and design services, we
provide customers with a complete product design that can be manufactured
efficiently.

Prototyping and new product introduction services. We provide rapid
assembly of prototype products within our dedicated, streamlined New Product
Introduction Plus centers. We supplement our prototype assembly services with
value-added services, including printed circuit board design, materials
management, manufacturing defects analysis, analysis of the manufacturability
and testability of a design, test implementation and pilot production runs
leading to volume production. These services link our engineering organization,
our customers' engineering organizations and our volume manufacturing
organization. This link facilitates an efficient transition to manufacturing. We
believe that these services provide significant value to our customers by
accelerating their products' time-to-market schedule.

Test development and product testing. Because product functionality has
driven components and assembly techniques to become increasingly complex, there
is a need to design and assemble increasingly complex in-circuit and functional
test equipment for electronic products and assemblies. Our internal development
of this test equipment allows us to rapidly implement test solutions and
efficiently test printed circuit assemblies, subassemblies and product and
system assemblies. We also develop and utilize specialized equipment that allows
us to environmentally stress test products during functional testing to assure
reliability. We believe that the design and production of test equipment is an
important factor in our ability to provide technology-driven products of
consistent and high quality.

Manufacturing and assembly. We provide turnkey manufacturing services for a
variety of electronic products to diverse industries. These services include
developing and implementing a materials strategy that meets customers' demand
and flexibility requirements, assembling printed circuit assemblies utilizing a
wide range of assembly technologies, building and configuring final product and
system boxes and testing assemblies to meet customers' requirements. We have the
expertise to assemble very complex electronic products that utilize multiple
printed circuit boards and subassemblies. These complex products are typically
configured to fulfill unique customer requirements and many are shipped directly
to our customers' end users. In addition, we have developed special processes
and tools to meet industry-specific requirements. Among these are the tools and
processes to assemble finished medical devices that meet U.S. Food and Drug
Administration Quality Systems Regulation requirements and similar regulatory
requirements of other countries.

After-market support. We provide service support for manufactured products.
In this context, supported products, which may or may not be under the
customer's warranty, may be returned for repairs or upgrades at the customer's
discretion.

RECENT COMBINATIONS AND ACQUISITIONS

Since fiscal 1998, we have completed six acquisitions that have added
facilities totaling approximately 539,000 square feet and over 2,400 new
employees. We have actively pursued combinations and acquisitions to expand our
geographic reach, increase our design, engineering and manufacturing capability

S-15
<PAGE> 18

and breadth of service offerings and strengthen and broaden our customer
relationships. Since fiscal 1998, we have completed the following acquisitions:

<TABLE>
<CAPTION>
ACQUIRED COMPANY/ FACILITIES
DATE OPERATIONS SQUARE FOOTAGE EMPLOYEES LOCATION(S)
---- -------------------------------- -------------- --------- -------------------
<S> <C> <C> <C> <C>
July 2000............ Keltek (Holdings) Limited 77,000 461 Kelso, Scotland
Maldon, England
May 2000............. Turnkey electronics 250,000 1,394 Juarez, Mexico
manufacturing operations of
Elamex, S.A. de C.V.
April 2000........... Agility, Incorporated 25,000 98 Ayer, Massachusetts
December 1999........ Printed circuit board operations - 45 Everett, Washington(1)
of Intermec Technologies
Corporation
September 1999....... Printed circuit board operations 25,000 125 Wheeling, Illinois
of Shure, Incorporated
July 1999............ SeaMED Corporation 162,000 301 Bothell, Washington
</TABLE>

------------

(1) Combined with our existing Bothell, Washington operations.

CUSTOMERS AND INDUSTRIES SERVED

We provide services to a wide variety of customers, ranging from large
multi-national companies to smaller emerging technology companies, including
start-ups. Because of the variety of services we offer, our flexibility in
design and manufacturing and our ability to respond to customer needs in a
timely fashion, we believe that we are well-positioned to offer our services to
customers in most market segments. For many customers, we serve both a design
and production function, thereby permitting customers to concentrate on concept
development, distribution and marketing, while accelerating their time to
market, reducing their investment in manufacturing capacity and optimizing total
product cost.

During fiscal 1999, we provided services to approximately 140 customers,
ranging from emerging technology companies such as Equipe Communications, Gotham
Networks, and Sitara Networks to industry leaders such as Lucent Technologies,
Cisco Systems, General Electric, Unisys, Siemens, Honeywell and Johnson &
Johnson. Lucent Technologies and General Electric represented over 10 percent of
our net sales for the periods set forth below:

<TABLE>
<CAPTION>
PERCENTAGE OF NET SALES
---------------------------------
FISCAL YEAR
------------ NINE MONTHS ENDED
CUSTOMER 1998 1999 JUNE 30, 2000
-------- ---- ---- -----------------
<S> <C> <C> <C>
Lucent Technologies......................................... * 16% 24%
General Electric............................................ * 12% 11%
</TABLE>

------------
* represents sales less than 10 percent

Many of our large customers, including Lucent Technologies and General
Electric, contract independently through multiple divisions, subsidiaries,
production facilities or locations. We believe that in most cases our sales to
one such subsidiary, division, facility or location are not dependent on sales
to others. Although the complete loss of any major customer could have a
significant negative impact on us, we do not believe the loss of all divisions,
subsidiaries, facilities or locations of a major customer to be likely.

S-16
<PAGE> 19

We provided services within the following industries in the following
proportions:

<TABLE>
<CAPTION>
PERCENTAGE OF NET SALES
---------------------------------
FISCAL YEAR
------------ NINE MONTHS ENDED
INDUSTRY 1998 1999 JUNE 30, 2000
-------- ---- ---- -----------------
<S> <C> <C> <C>
Networking/Telecommunications............................... 15% 24% 35%
Medical..................................................... 29% 31% 29%
Industrial.................................................. 20% 23% 19%
Computer.................................................... 23% 14% 10%
Transportation/Other........................................ 13% 8% 7%
</TABLE>

MATERIALS AND SUPPLIERS

We purchase raw materials and electronic components from manufacturers and
distribution companies. The key electronic components we purchase include
printed circuit boards, specialized components such as application-specific
integrated circuits, semi-conductors, interconnect products, electronic
subassemblies (including memory modules, power supply modules and cable and wire
harnesses), resistors and capacitors. Along with these electronic components, we
also purchase components for use in higher-level assembly and manufacturing.
These components include sheet metal fabrications, aluminum extrusions, die
castings and various other hardware and fastener components. These components
range from standard to highly customized and they vary widely in terms of market
volatility and price.

From time to time, allocation of components becomes an integral part of the
electronics industry, and component shortages can occur with respect to
particular components. In response, we actively manage our business in a way
that minimizes our exposure to materials and component shortages. We have
developed a corporate procurement organization whose primary purpose is to
create strong supplier alliances to ensure, as much as possible, a steady flow
of components at competitive prices. Because we design products and can
influence what components are used in some new products, components
manufacturers often provide us with a greater amount of materials and
components, even during shortages. We have also established and continue to
expand strategic relationships with international purchasing offices, and we
attempt to leverage our design position with suppliers. Beyond this, we have
undertaken a series of flexibility initiatives, including the utilization of
in-plant stores, point-of-use programs, assured supply programs and similar
efforts. All of these undertakings seek to improve our overall supply chain
flexibility and to accommodate our growth plans.

SALES AND MARKETING

We market our services primarily through our sales and marketing
organization of 65 people, which includes salespeople, strategic customer
managers, technology specialists and advertising and other corporate
communications personnel. Our sales and marketing efforts focus on generating
new customers and pursuing profitable opportunities. We use our ability to
provide a full range of product realization services as a marketing tool, and
our technology specialists participate in marketing through direct customer
contact and participation in industry symposia and seminars. Our sales force is
integrated with the rest of our business and is aligned geographically within
important technology corridors. We support our sales and marketing efforts with
in-depth industry research.

COMPETITION

The market for the products and services we provide is highly competitive.
We compete primarily on the basis of engineering, testing and production
capability, technological capabilities and the capacity for responsiveness,
quality and price. There are many competitors in the electronics design and
assembly industry. Larger and more geographically diverse competitors have
substantially more resources than we do. Other, smaller competitors compete only
in narrow, specific areas of our business. We also compete against companies
that design or manufacture items in-house rather than by outsourcing. In
addition, we

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<PAGE> 20

compete against foreign, low-labor-cost manufacturers. This foreign,
low-labor-cost competition tends to focus on commodity and consumer-related
products, which is not our primary focus.

FACILITIES

Our facilities comprise an integrated network of technology and
manufacturing centers, with corporate headquarters located in our engineering
facility in Neenah, Wisconsin. We own or lease facilities with approximately
1.25 million square feet of capacity. This includes approximately 900,000 square
feet in the United States, approximately 250,000 square feet in Mexico and
approximately 77,000 square feet in Europe. We are also undertaking expansion
projects to expand significantly several of our existing facilities. The
geographic diversity of our technology and manufacturing centers allows us to
offer services from locations near our customers and major electronics markets.
We believe that this approach reduces material and transportation costs,
simplifies logistics and communications and improves inventory management. This
enables us to provide customers with a more complete, cost-effective solution.

Our facilities are described in the following table:

<TABLE>
<CAPTION>
LOCATION TYPE SIZE (SQ. FT.) OWNED/LEASED
-------- ---------------- -------------- ------------
<S> <C> <C> <C>
Neenah, Wisconsin(1).............................. Manufacturing 305,000 Leased
Juarez, Mexico(1)................................. Manufacturing 250,000 Leased
Neenah, Wisconsin(1).............................. Manufacturing 95,000 Owned
Richmond, Kentucky(2)............................. Manufacturing 45,000 Owned
Maldon, England................................... Manufacturing 40,000 Owned
Kelso, Scotland(3)................................ Manufacturing 37,000 Owned
Wheeling, Illinois(4)............................. Manufacturing 25,000 Leased
Appleton, Wisconsin(5)............................ NPI Plus Center 67,000 Owned
Bothell, Washington............................... NPI Plus Center 60,000 Leased
Ayer, Massachusetts(6)............................ NPI Plus Center 25,000 Leased
Redmond, Washington............................... NPI Plus Center 21,000 Leased
Blaine, Minnesota................................. NPI Plus Center 14,000 Owned
Milpitas, California.............................. NPI Plus Center 5,000 Leased
Neenah, Wisconsin(7).............................. Engineering 45,000 Owned
Bothell, Washington............................... Engineering 81,000 Leased
Raleigh, North Carolina........................... Engineering 14,000 Leased
Louisville, Colorado.............................. Engineering 14,000 Leased
Neenah, Wisconsin................................. Office/Warehouse 100,000 Leased
Redmond, Washington(8)............................ Office/Warehouse 60,000 Leased
Bothell, Washington(8)............................ Office/Warehouse 10,000 Leased
Blaine, Minnesota................................. Office/Warehouse 5,200 Leased
El Paso, Texas.................................... Office/Warehouse 5,000 Leased
</TABLE>

------------
(1) Includes more than one building.

(2) We are expanding this facility by approximately 55,000 square feet, which is
expected to be completed by July 2001.

(3) These operations are moving to a new 57,000 square-foot facility, which is
scheduled to be completed by October 2000.

(4) These operations are moving to a new 135,000 square-foot leased facility,
which is expected to be completed by August 2001.

(5) We acquired this facility in July 2000 and expect operations to commence in
October 2000.

(6) We are expanding this facility by approximately 40,000 square feet, which is
expected to be completed by October 2000.

(7) We are expanding this facility by approximately 60,000 square feet, which is
expected to be completed by October 2000.

(8) These buildings are being subleased to an unrelated third party and not used
in our business operations.

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<PAGE> 21

EMPLOYEES

Our employees are one of our primary strengths, and we make considerable
efforts to maintain a well-qualified staff. As we have grown, we have been able
to offer enhanced career opportunities to many of our employees. Our human
resources department identifies career objectives and monitors specific skill
development for employees with management and technical potential for
advancement. We invest heavily in training at all levels to ensure that
employees are well-trained. We operate a policy of involvement and consultation
with employees in every facility and strive for continuous improvement at all
levels.

As of September 2000, we employed approximately 5,300 full-time employees.
Given the growth of our business and the quick response time required by our
customers, we seek to maintain flexibility to scale our operations as necessary
to maximize efficiency. To do so, we use skilled temporary labor. In Europe,
approximately 60 of our employees are covered by union agreements. These union
agreements are typically renewed at the beginning of each year, although in a
few cases they may last two or more years. None of our employees in the United
States and Mexico is covered by union agreements. We have no history of labor
disputes at any of our facilities. We believe that our employee relationships
are good.

S-19
<PAGE> 22

MANAGEMENT

The following table sets forth our directors and executive officers, their
ages and the positions currently held by each person:

<TABLE>
<CAPTION>
NAME AGE POSITION
---- --- --------
<S> <C> <C>
Peter Strandwitz............................... 63 Chairman, Chief Executive Officer and Director
John L. Nussbaum............................... 58 President, Chief Operating Officer and Director
Dean A. Foate.................................. 41 Executive Vice President and Director
Thomas B. Sabol................................ 41 Senior Vice President and Chief Financial
Officer
Joseph D. Kaufman.............................. 43 Vice President, Secretary and General Counsel
Lisa M. Kelley................................. 33 Vice President--Finance, Treasurer and Chief
Accounting Officer
J. Robert Kronser.............................. 41 Vice President--Sales and Marketing
Paul A. Morris................................. 39 Vice President--Information Systems Development
Charles C. Williams............................ 64 Vice President
David J. Drury................................. 52 Director
Harold R. Miller............................... 72 Director
Thomas J. Prosser.............................. 63 Director
Agustin A. Ramirez............................. 54 Director
Jan K. Ver Hagen............................... 62 Director
</TABLE>

Peter Strandwitz is a co-founder of Plexus and has served as Chairman of
the Board, Chief Executive Officer and a director since 1979.

John L. Nussbaum is a co-founder of Plexus and has served as President and
a director since 1980, and Chief Operating Officer since 1996.

Dean A. Foate joined Plexus in 1984 and has served as President of Plexus
Technology Group since 1995, Executive Vice President of Plexus since 1999 and a
director since March 2000.

Thomas B. Sabol joined Plexus in 1996 and has served as Senior Vice
President since May 2000. Previously, he served as Vice President and General
Auditor for Kemper Corporation and before that as Business Assurance Manager for
Coopers & Lybrand.

Joseph D. Kaufman joined Plexus in 1986 and has served as Vice President,
Secretary and General Counsel of Plexus since 1990.

Lisa M. Kelley joined Plexus in 1992 and has served as Treasurer since
1998, and Vice President--Finance since May 2000.

J. Robert Kronser joined Plexus in 1981 and has served as Vice President of
Sales and Marketing since May 2000.

Paul A. Morris joined Plexus in 1984 and has served as Vice President of
Information Systems Development since May 2000.

Charles C. Williams joined Plexus in 1982 and has been a Vice President
since 1989.

David J. Drury, a director of Plexus, has been the President of Pablocki &
Sons LLC, an exterior and interior sign systems company, since 1999. Previously,
he was an independent consultant and was President of Stolper-Fabralloy Co. LLC,
an engine component manufacturing company.

Harold R. Miller, a director of Plexus, is retired, having previously
served as Chairman of the Board and Chief Executive Officer of Marathon
Engineers/Architects/Planners, Inc., a provider of architectural and engineering
services.

Thomas J. Prosser, a director of Plexus, has been the Chairman and Chief
Executive Officer of Menasha Corporation, a manufacturer of paper and plastic
products, since 1999. In addition, he is an officer of Robert W. Baird & Co.
Incorporated, a provider of brokerage and financial services.

Agustin A. Ramirez, a director of Plexus, is the President, Chairman and
Chief Executive Officer of HUSCO International, Inc., a manufacturer of
hydraulic and electrohydraulic controls.

Jan K. Ver Hagen, a director of Plexus, has served as Senior Vice President
of Corporate Projects of Emerson Electric Co. since 1999. He also serves as a
director and non-executive Chairman of Wolverine Tube, Inc., a manufacturing
company, and Vice Chairman of United Dominion Industries, also a manufacturing
company.

S-20
<PAGE> 23

UNITED STATES FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS

The following summary describes the material U.S. federal income and estate
tax consequences of the ownership and disposition of our common stock by a
non-U.S. holder who acquires and owns our shares as a capital asset within the
meaning of section 1221 of the Internal Revenue Code. A non-U.S. holder is any
person other than:

- a citizen or resident of the United States

- a corporation, partnership or other entity created or organized in the
United States or under the laws of the United States or of any state

- an estate whose income is includable in gross income for U.S. federal
income tax purposes regardless of its source

- a trust if a court within the United States is able to exercise primary
supervision over the administration of the trust and one or more U.S.
persons have the authority to control all substantial decisions of the
trust.

If an entity treated as a partnership for U.S. tax purposes holds our
common stock, the tax treatment of each partner will generally depend upon the
status of the partner and upon the activities of the partnership. If you are a
partner of a partnership holding our common stock, you should consult your tax
advisor.

For purposes of the withholding tax on dividends discussed below, a
non-resident fiduciary of an estate or trust will be considered a non-U.S.
holder. An individual may, subject to limited exceptions, be deemed to be a
resident alien, as opposed to a non-resident alien, by being present in the
United States on at least 31 days in the calendar year and at least 183 days
during a three-year period ending in the current calendar year. All of the days
in which an individual is present in the current year, one third of the days in
which an individual is present in the preceding year and one-sixth of the days
in which an individual is present in the second preceding year are counted for
purposes of this calculation. Resident aliens are subject to U.S. federal tax as
if they were U.S. citizens and, thus, are not non-U.S. holders for purposes of
this discussion.

This discussion does not consider specific facts and circumstances that may
be relevant to a particular non-U.S. holder's tax position, including the fact
that in the case of a non-U.S. holder that is a partnership, the U.S. tax
consequences of holding and disposing of common stock may be affected by
determinations made at the partner level. This discussion also does not consider
U.S. state and local or non-U.S. tax consequences. Further, it does not consider
non-U.S. holders subject to special tax treatment under the U.S. federal income
tax laws, including U.S. expatriates, banks and insurance companies, dealers in
securities and holders of securities held as part of a straddle, hedge or
conversion transaction. In addition, persons that hold the common stock through
hybrid entities may be subject to special rules and may not be entitled to the
benefits of a U.S. income tax treaty. A hybrid entity is an entity treated as a
partnership for U.S. tax purposes and as a corporation for foreign law purposes.
The following discussion is based on provisions of the Internal Revenue Code and
administrative and judicial interpretations as of the date of this prospectus
supplement, all of which are subject to change, possibly on a retroactive basis.
Any change could affect the continuing validity of this discussion. THE
FOLLOWING SUMMARY IS FOR GENERAL INFORMATION. IF YOU ARE A NON-U.S. HOLDER, WE
URGE YOU TO CONSULT A TAX ADVISOR ABOUT THE U.S. FEDERAL TAX CONSEQUENCES OF
HOLDING AND DISPOSING OF OUR COMMON STOCK, AS WELL AS ANY TAX CONSEQUENCES THAT
MAY ARISE UNDER THE LAWS OF ANY U.S. STATE, LOCAL OR OTHER NON-U.S. TAXING
JURISDICTION.

Dividends. In general, if we have tax earnings and profits at the time of
any payment of dividends, the gross amount of any dividends paid to a non-U.S.
holder will be subject to withholding of U.S. federal income tax at a 30 percent
rate unless this rate is reduced by an applicable income tax treaty. Dividends
that are effectively connected with the holder's conduct of a trade or business
in the United States, or, if a tax treaty applies, attributable to a permanent
establishment, or in the case of an individual, a fixed base, in the United
States ("U.S. trade or business income") are generally subject to U.S. federal
income tax at

S-21
<PAGE> 24

regular rates and not subject to withholding if the non-U.S. holder files the
appropriate U.S. Internal Revenue form with the payor. Any U.S. trade or
business income received by a non-U.S. corporation also may be subject to an
additional "branch profits tax" at a 30 percent rate, or any lower rate that may
be applicable under an income tax treaty.

Under current law, dividends paid to an address in a foreign country are
presumed, absent actual knowledge to the contrary, to be paid to a resident of
that country for purposes of the withholding discussed above. The same
presumption applies under the current interpretation of U.S. Treasury
regulations, for purposes of determining the applicability of a tax treaty rate.
Under final U.S. Treasury regulations, effective January 1, 2001, however, a
non-U.S. holder of common stock who wishes to claim the benefit of an applicable
treaty rate would have to satisfy certification and other requirements,
including filing a Form W-8 BEN that contains the holder's name and address.

A non-U.S. holder of common stock that is eligible for a reduced rate of
U.S. withholding tax pursuant to an income tax treaty may obtain a refund of any
excess amounts currently withheld by filing an appropriate claim for a refund
with the U.S. Internal Revenue Service.

Disposition Of Common Stock. Except as described below, a non-U.S. holder
generally will not be subject to U.S. federal income tax for gain recognized on
a disposition of common stock, if:

- the gain is not U.S. trade or business income

- the non-U.S. holder is an individual who is not present in the United
States for 183 or more days in the taxable year of the disposition and
who meets other statutory requirements

- the non-U.S. holder is not subject to tax under provisions of U.S. tax
law applicable to U.S. expatriates.

We have not been and do not become a "United States real property holding
corporation" for U.S. federal income tax purposes.

We believe that we have not been and are not likely to become, a United
States real property holding corporation. However, we cannot assure you that we
will not be a United States real property corporation when a non-U.S. holder
sells its common stock.

Federal Estate Taxes. In general, an individual who is a non-U.S. holder
for U.S. estate tax purposes will be liable for U.S. federal estate tax if the
fair market value of property included in the individual's taxable estate for
U.S. federal estate tax purposes exceeds the statutory threshold amount. For
these purposes, common stock owned or treated as owned, by an individual who is
a non-U.S. holder at the time of death will be included in the individual's
gross estate for U.S. federal tax purposes unless an applicable estate tax
treaty provides otherwise.

United States Information Reporting Requirements And Backup Withholding
Tax. We have to report annually to the Internal Revenue Service and to each
non-U.S. holder the amount of dividends paid to, and the tax withheld from, each
non-U.S. holder. These reporting requirements apply regardless of whether
withholding was reduced or eliminated by a tax treaty. Copies of these
information returns may also be made available under the provisions of a
specific treaty or agreement to the tax authorities in the country in which the
non-U.S. holder resides. Under current regulations, the U.S. backup withholding
tax, which generally is a withholding tax imposed at the rate of 31 percent on
some payments to persons that fail to comply with the information reporting
requirements, will generally not apply to dividends paid on the common stock to
a non-U.S. holder at an address outside the United States. Under final Treasury
regulations, effective January 1, 2001, a non-U.S. holder generally would not be
subject to backup withholding at a 31 percent rate if the beneficial owner
certifies to that owner's foreign status on a valid Form W-8 BEN.

Non-U.S. holders will not be subject to information reporting or backup
withholding on the payment of proceeds from the disposition of common stock
effected by a foreign office of a foreign broker. If the broker is a U.S. person
or a U.S. related person, information reporting, but not backup withholding,
would

S-22
<PAGE> 25

apply unless the broker received a signed statement from the owner, certifying
its foreign status or otherwise establishing an exemption, or the broker had
documentary evidence in its files as to the non-U.S. holder's foreign status and
the broker had no actual knowledge to the contrary. For this purpose, a "U.S.
related person" is:

- a controlled foreign corporation for U.S. federal income tax purposes

- a foreign person 50 percent or more of whose gross income from all
sources for the three-year period ending with the close of its taxable
year preceding the payment (or for the part of the period that the broker
has been in existence) is derived from activities that are effectively
connected with the conduct of a U.S. trade or business

- a foreign partnership that is either engaged in a U.S. trade or business
or in which U.S. persons hold more than 50 percent of the income or
capital interest

- certain U.S. branches of foreign banks or insurance companies.

Non-U.S. holders will be subject to information reporting and backup
withholding at a rate of 31 percent on payment of proceeds from the disposition
of common stock effected by, to or through the U.S. office of a broker, unless
the non-U.S. holder certifies as to its foreign status or otherwise establishes
an exemption. Any amounts withheld under the backup withholding rules from a
payment to a non-U.S. holder will be allowed as a credit against the non-U.S.
holder's U.S. federal income tax, and any amounts withheld in excess of the
non-U.S. holder's federal income tax liability will be refunded, if the required
information is furnished to the Internal Revenue Service.

S-23
<PAGE> 26

UNDERWRITING

We are offering the shares of common stock described in this prospectus
supplement through a number of underwriters. Robertson Stephens, Inc., SG Cowen
Securities Corporation, Thomas Weisel Partners LLC and Robert W. Baird & Co.
Incorporated are the representatives of the underwriters. We entered into an
underwriting agreement with the representatives. Subject to the terms and
conditions of the underwriting agreement, we agreed to sell to the underwriters,
and each underwriter separately agreed to purchase, the number of shares of
common stock listed next to its name at the public offering price, less the
underwriting discount described on the cover page of this prospectus supplement:

<TABLE>
<CAPTION>
UNDERWRITER NUMBER OF SHARES
----------- ----------------
<S> <C>
Robertson Stephens, Inc. ...................................
SG Cowen Securities Corporation.............................
Thomas Weisel Partners LLC..................................
Robert W. Baird & Co. Incorporated..........................
INTERNATIONAL UNDERWRITER
------------------------------------------------------------
Robertson Stephens International, Ltd.......................
SG Cowen Securities Corporation.............................
Thomas Weisel Partners LLC..................................
Robert W. Baird & Co. Incorporated..........................
---------
Total................................................ 3,000,000
=========
</TABLE>

The underwriting agreement provides that the underwriters must buy all of
these shares if they buy any of them. The underwriters will sell these shares to
the public when and if the underwriters buy them from us. The underwriters are
offering the common stock subject to a number of conditions, including:

- the underwriters' receipt and acceptance of the common stock from us

- the underwriters' right to reject orders in whole or in part.

The underwriters expect to deliver the shares of common stock to purchasers
on , 2000.

Over-Allotment Option

We have granted the underwriters an option to buy up to 450,000 additional
shares of our common stock at the same price per share as they are paying for
the shares shown in the table above. The underwriters may exercise this option
only to the extent that they sell more than the total number of shares shown in
the table above. The underwriters may exercise this option at any time within 30
days after the date of this prospectus supplement. To the extent that the
underwriters exercise this option, the underwriters will be obligated to
purchase the additional shares from us in the same proportions as they purchased
the shares shown in the table above. If purchased, these additional shares will
be sold by the underwriters on the same terms as those on which the other shares
are sold.

Listing

Our common stock is quoted on the Nasdaq National Market under the symbol
"PLXS."

Underwriting Discounts and Commissions
The underwriting discount is the difference between the price the
underwriters pay to us and the price at which the underwriters initially offer
the shares to the public. The size of the underwriting discount is

S-24
<PAGE> 27

determined through an arms-length negotiation between us and the
representatives. The following table shows the per share and total underwriting
discount we will allow to the underwriters. These amounts are shown assuming no
exercise and full exercise of the underwriters' over-allotment option described
above:

<TABLE>
<CAPTION>
TOTAL
---------------------------------------
NO FULL
EXERCISE OF EXERCISE OF
PER SHARE OPTION OPTION
--------- ----------- -----------
<S> <C> <C> <C>
Public Offering Price....................................... $ $ $
Underwriting discount allowed by us......................... $ $ $
Proceeds, before expenses, to us............................ $ $ $
</TABLE>

The expenses of this offering, not including the underwriting discount, are
estimated to be approximately $600,000. Expenses include the Securities and
Exchange Commission filing fee, printing expenses, legal and accounting fees,
transfer agent and registrar fees and other miscellaneous fees and expenses. All
of the expenses of this offering will be paid by us.

Lock-up Agreements
We and our executive officers and directors, have agreed, with exceptions,
not to sell or transfer any shares of our common stock for 90 days after the
date of this prospectus without first obtaining the written consent of Robertson
Stephens, Inc. Specifically, we and these other individuals have agreed not to,
directly or indirectly:

- offer to sell, contract to sell, or otherwise sell or dispose of any
shares of our common stock

- loan, pledge or grant any rights with respect to any shares of our common
stock

- engage in any hedging or other transaction that might result in a
disposition of shares of our common stock by anyone

- execute any short sale, whether or not against the box

- purchase, sell or grant any put or call option or other right with
respect to our common stock or with respect to any security other than a
broad-based market basket or index that includes, relates to or derives
any significant part of its value from our common stock.

These lock-up agreements apply to shares of our common stock and also to
any options or warrants to purchase any shares of our common stock or any
securities convertible into or exchangeable for shares of our common stock.
These lock-up agreements apply to all such securities that are owned or later
acquired by the persons executing the agreements, except for securities acquired
on the open market. In addition, we have agreed with Robertson Stephens, Inc.
that, to the extent that we have separate lock-up agreements with some of our
shareholders, we will not consent to the shareholders' disposition of any shares
subject to those separate lock-up agreements prior to the expiration of the
lock-up period. However, Robertson Stephens, Inc. may release any of us from
these agreements at any time during the 90-day period, in its sole discretion
and without notice, as to some or all of the shares covered by these agreements.
Currently, there are no agreements between the representatives and us or any of
our shareholders to release any of us from the lock-up agreements during such
90-day period.

Indemnification of the Underwriters
We will indemnify the underwriters against some civil liabilities,
including liabilities under the Securities Act and liabilities arising from
breaches of our representations and warranties contained in the underwriting
agreement. If we are unable to provide this indemnification, we will contribute
to payments the underwriters may be required to make in respect of those
liabilities, which means that we will reimburse the underwriters for a portion
of their payments. The relative size of our payments will be based upon the
relative benefits received by us and the underwriters from the offering of our
shares. The payment amounts may also be based on the parties' relative degree of
fault in producing the original liability.

S-25
<PAGE> 28

Dealers' Compensation
The underwriters initially will offer our shares to the public at the price
specified on the cover page of this prospectus. The underwriters may allow to
selected dealers a concession of not more than $ per share. The
underwriters may also allow, and any other dealers may reallow, a concession of
not more than $ per share to some other dealers. If all the shares are
not sold at the public offering price, the underwriters may change the public
offering price and the other selling terms. A change in the public offering
price will not affect the amount of proceeds that we receive.

Discretionary Accounts
The underwriters have advised us that they do not expect to sell more than
5 percent of the total number of shares in this offering to accounts over which
they exercise discretionary authority.

Stabilization and Other Transactions
The rules of the Securities and Exchange Commission generally prohibit the
underwriters from trading in our common stock on the open market during this
offering. However, the underwriters are allowed to engage in some open market
transactions and other activities during this offering that may cause the market
price of our common stock to be above or below that which would otherwise
prevail in the open market. These activities may include stabilization, short
sales and over-allotments, syndicate covering transactions and penalty bids.

- Stabilizing transactions consist of bids or purchases made by the lead
representative for the purpose of preventing or slowing a decline in the
market price of our common stock while this offering is in progress.

- Short sales and over-allotments occur when the representatives, on behalf
of the underwriting syndicate, sell more of our shares than they purchase
from us in this offering. "Covered" short sales are sales made in an
amount not greater than the underwriters' option to purchase additional
shares from us in the offering. The underwriters may close out any
covered short position either by exercising that option to purchase
shares from us or by purchasing shares in the open market. In determining
the source of shares to close out a covered short position, the
underwriters will consider, among other things, the prevailing market
price per share compared to the exercise price per share of their option.
"Naked" short sales are any sales by the underwriters in excess of their
option. The underwriters must close out any naked short position by
purchasing shares in the open market, potentially including purchases
made as stabilizing transactions. For this reason, a naked short position
is more likely to be created if the underwriters are concerned that there
may be downward pressure on the price of the common stock in the open
market after pricing that could adversely affect investors who purchase
in the offering.

- Syndicate covering transactions are bids for or purchases of our common
stock on the open market by the representatives on behalf of the
underwriters in order to reduce a short position incurred by the
representatives on behalf of the underwriters. Similar to other purchase
transactions, syndicate covering transactions may have the effect of
raising or maintaining the market price of our common stock or preventing
or retarding a decline in the market price of our common stock. As a
result, the price of our common stock may be higher than the price that
might otherwise exist in the open market.

- A penalty bid is an arrangement permitting the representatives to reclaim
the selling concession that would otherwise accrue to an underwriter if
the common stock originally sold by that underwriter was later
repurchased by the representatives and therefore was not effectively sold
to the public by such underwriter.

If the underwriters commence these activities, they may discontinue them at
any time without notice. The underwriters may carry out these transactions on
the Nasdaq National Market, in the over-the-counter market or otherwise.

S-26
<PAGE> 29

Passive Market Making
Following the pricing of this offering, and until the commencement of any
stabilizing bid, underwriters and dealers who are qualified market makers on the
Nasdaq National Market may engage in passive market making transactions. Passive
market making is allowed during the period when the Securities and Exchange
Commission's rules would otherwise prohibit market activity by the underwriters
and dealers who are participating in this offering. Passive market makers must
comply with applicable volume and price limitations and must be identified as
such. In general, a passive market maker must display its bid at a price not in
excess of the highest independent bid for our common stock; but if all
independent bids are lowered below the passive market maker's bid, the passive
market maker must also lower its bid once it exceeds specified purchase limits.
Net purchases by a passive market maker on each day are limited to a specified
percentage of the passive market maker's average daily trading volume in our
common stock during a specified period and must be discontinued when such limit
is reached. Underwriters and dealers are not required to engage in passive
market making and may end passive market making activities at any time.

Thomas Weisel Partners

Thomas Weisel Partners LLC, one of the representatives of the underwriters,
was organized and registered as a broker-dealer in December 1998. Since December
1998, Thomas Weisel Partners has been named as a lead or co-manager on 177 filed
public offerings of equity securities, of which 141 have been completed, and has
acted as syndicate member in an additional 117 public offerings of equity
securities. Thomas Weisel Partners does not have any material relationship with
Plexus or any of its officers, directors or controlling persons, except with
respect to its contractual relationship with Plexus pursuant to the underwriting
agreement entered into in connection with this offering.

Other Relationships

In the ordinary course of their business, the underwriters or their
affiliates have engaged in or provided investment or commercial banking and
financial advisory services to us, for which they have received customary
compensation and expense reimbursement, and may do so again in the future. In
addition, Thomas J. Prosser, one of our directors, is a Senior Vice
President--Investment Banking of Robert W. Baird & Co. Incorporated, one of the
representatives of the underwriters. Mr. Prosser has taken a leave of absence
from Robert W. Baird & Co. Incorporated and currently serves as Chairman and
Chief Executive Officer of Menasha Corporation, a manufacturer of paper and
plastic products.

LEGAL MATTERS

The validity of the shares of common stock to be sold pursuant to this
prospectus supplement will be passed upon for us by Quarles & Brady LLP,
Milwaukee, Wisconsin, counsel to the Company. As of September 19, 2000, members
of Quarles & Brady LLP providing services to Plexus in connection with the
offering held 1,000 shares of Plexus common stock. The underwriters have been
represented by Jones, Day, Reavis & Pogue, Chicago, Illinois.

S-27
<PAGE> 30

PLEXUS CORP.

LIST OF FINANCIAL STATEMENTS

SEPTEMBER 30, 1999

CONTENTS

<TABLE>
<CAPTION>
PAGES
-----
<S> <C>
Report of Independent Accountants........................... F-2
Consolidated Financial Statements:
Consolidated Statements of Operations for the three years
ended September 30, 1999, 1998 and 1997................ F-3
Consolidated Balance Sheets as of September 30, 1999 and
1998................................................... F-4
Consolidated Statements of Stockholders' Equity for the
three years ended September 30, 1999, 1998 and 1997.... F-5
Consolidated Statements of Cash Flows for the three years
ended September 30, 1999, 1998 and 1997................ F-6
Notes to Consolidated Financial Statements................ F-7
</TABLE>

F-1
<PAGE> 31

REPORT OF INDEPENDENT ACCOUNTANTS

To the Shareholders and
Board of Directors
Plexus Corp.:

In our opinion, based on our audits and the report of other auditors, the
accompanying consolidated balance sheets and the related consolidated statements
of operations, of stockholders' equity and of cash flows present fairly, in all
material respects, the financial position of Plexus Corp. and subsidiaries at
September 30, 1999 and 1998 and the results of their operations and their cash
flows for each of the three years in the period ended September 30, 1999 in
conformity with generally accepted accounting principles. These financial
statements are the responsibility of the Company's management; our
responsibility is to express an opinion on these financial statements based on
our audits. The consolidated financial statements give retroactive effect to the
merger of SeaMED Corporation on July 23, 1999 in a transaction accounted for as
a pooling of interests, as described in Notes 1 and 8 of notes to consolidated
financial statements. We did not audit the financial statements of SeaMED
Corporation, which statements reflect, after restatement for certain adjustments
as explained in Note 8 of notes to consolidated financial statements, total
assets of $42.9 million as of June 30, 1998 and total revenues of $70.0 million
and $52.1 million for the years ended June 30, 1998 and 1997, respectively.
Those statements were audited by other auditors whose report thereon has been
furnished to us, and our opinion expressed herein, insofar as it relates to the
amounts included for SeaMED Corporation is based solely on the report of the
other auditors. We conducted our audits of these statements in accordance with
generally accepted auditing standards, which require that we plan and perform
the audit to obtain reasonable assurance about whether the financial statements
are free of material misstatement. An audit includes examining, on a test basis,
evidence supporting the amounts and disclosures in the financial statements,
assessing the accounting principles used and significant estimates made by
management, and evaluating the overall financial statement presentation. We
believe that our audits and the report of other auditors provide a reasonable
basis for the opinion expressed above.

PricewaterhouseCoopers LLP
Milwaukee, Wisconsin

October 26, 1999, except for certain

information in Note 6, as to which

the date is August 31, 2000

F-2
<PAGE> 32

PLEXUS CORP. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS
FOR THE YEARS ENDED SEPTEMBER 30, 1999, 1998 AND 1997
(IN THOUSANDS, EXCEPT PER SHARE DATA)

<TABLE>
<CAPTION>
1999 1998 1997
-------- -------- --------
<S> <C> <C> <C>
Net sales................................................... $492,414 $466,795 $438,565
Cost of sales............................................... 426,005 406,648 387,333
-------- -------- --------
Gross profit......................................... 66,409 60,147 51,232
Operating expenses:
Selling and administrative expenses....................... 26,443 23,754 20,463
Plant closing, relocation and severance................... 981 -- --
Merger costs.............................................. 4,557 -- --
-------- -------- --------
31,981 23,754 20,463
-------- -------- --------
Operating income..................................... 34,428 36,393 30,769
Other income (expense):
Interest expense.......................................... (274) (86) (1,014)
Miscellaneous............................................. 1,995 975 1,160
-------- -------- --------
Income before income taxes........................... 36,149 37,282 30,915
Income taxes................................................ 15,838 14,345 12,022
-------- -------- --------
Net income........................................... $ 20,311 $ 22,937 $ 18,893
======== ======== ========
Earnings per share:
Basic.................................................. $ 0.59 $ 0.68 $ 0.60
======== ======== ========
Diluted................................................ $ 0.55 $ 0.63 $ 0.54
======== ======== ========
Weighted average shares outstanding:
Basic.................................................. 34,646 33,688 30,732
Diluted................................................ 37,021 36,196 35,116
</TABLE>

The accompanying notes are an integral part of these consolidated financial
statements.

F-3
<PAGE> 33

PLEXUS CORP. AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS
AS OF SEPTEMBER 30, 1999 AND 1998
(IN THOUSANDS EXCEPT PER SHARE DATA)

<TABLE>
<CAPTION>
1999 1998
-------- --------
<S> <C> <C>
ASSETS
Current assets:
Cash and cash equivalents................................. $ 15,906 $ 24,106
Short-term investments.................................... 17,224 5,517
Accounts receivable, net of allowance of $773 and $1,011,
respectively........................................... 69,318 61,622
Inventories............................................... 79,017 57,321
Deferred income taxes..................................... 6,370 5,077
Prepaid expenses and other................................ 3,562 2,201
-------- --------
Total current assets................................. 191,397 155,844
Property, plant and equipment, net.......................... 35,868 26,517
Other....................................................... 2,371 1,993
-------- --------
Total assets......................................... $229,636 $184,354
======== ========
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Current portion of long-term debt......................... $ 10 $ 672
Accounts payable.......................................... 55,928 41,272
Customer deposits......................................... 8,650 6,635
Accrued liabilities:
Salaries and wages..................................... 9,820 8,447
Other.................................................. 6,578 7,659
-------- --------
Total current liabilities............................ 80,986 64,685
Long-term debt.............................................. 142 2,587
Deferred income taxes....................................... 215 700
Other liabilities........................................... 1,890 519
Stockholders' equity:
Preferred stock, $.01 par value, 5,000 shares authorized,
none issued or outstanding............................. -- --
Common stock, $.01 par value, 60,000 shares authorized,
35,090 and 17,016 issued, respectively (Note 6)........ 351 170
Additional paid-in capital................................ 51,249 42,478
Note receivable, officer.................................. -- (75)
Retained earnings......................................... 94,803 73,795
Treasury stock, at cost, 0 and 29 shares, respectively.... -- (505)
-------- --------
146,403 115,863
-------- --------
Total liabilities and stockholders' equity........... $229,636 $184,354
======== ========
</TABLE>

The accompanying notes are an integral part of these consolidated financial
statements.

F-4
<PAGE> 34

PLEXUS CORP. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY
FOR THE YEARS ENDED SEPTEMBER 30, 1999, 1998 AND 1997
(IN THOUSANDS)

<TABLE>
<CAPTION>
COMMON STOCK ADDITIONAL NOTE TREASURY STOCK
---------------- PAID-IN RECEIVABLE RETAINED -----------------
SHARES AMOUNT CAPITAL OFFICER EARNINGS SHARES AMOUNT
------ ------ ---------- ---------- -------- ------ -------
<S> <C> <C> <C> <C> <C> <C> <C>
Balances, October 1, 1996, as
previously reported........... 6,501 $ 65 $14,253 $ -- $33,699 -- $ --
Restatement for pooling of
interests with SeaMED......... 134 1 886 (75) (320) -- --
------ ---- ------- ---- ------- ---- -------
BALANCES AT OCTOBER 1, 1996,
RESTATED...................... 6,635 66 15,139 (75) 33,379 -- --
SeaMED initial public
offering...................... 306 3 14,820 -- -- -- --
Exercise of stock options,
including tax benefits........ 372 3 3,999 -- -- -- --
Preferred stock dividends....... -- -- (1,765) -- (338) -- --
Plexus preferred stock
conversion (Series A)......... 554 6 (6) -- -- -- --
SeaMED preferred stock
conversion (Class A, B, C and
D)............................ 587 6 5,274 -- -- -- --
Two-for-one common stock
split......................... 8,391 84 (84) -- -- -- --
Net income...................... -- -- -- -- 18,893 -- --
------ ---- ------- ---- ------- ---- -------
BALANCES, SEPTEMBER 30, 1997.... 16,845 168 37,377 (75) 51,934 -- --
Treasury stock purchased........ -- -- -- -- -- (214) (3,442)
Exercise of stock options,
including tax benefits........ 160 2 5,101 -- (1,024) 132 2,059
Common stock warrants issued.... 11 -- -- -- -- -- --
Other treasury stock
issuances..................... -- -- -- -- (52) 53 878
Net income...................... -- -- -- -- 22,937 -- --
------ ---- ------- ---- ------- ---- -------
BALANCES, SEPTEMBER 30, 1998.... 17,016 170 42,478 (75) 73,795 (29) (505)
Effect of SeaMED excluded
period........................ -- -- 16 -- 1,271 -- --
Treasury stock purchased........ -- -- -- -- -- (32) (1,160)
Exercise of stock options,
including tax benefit......... 529 5 8,931 -- (574) 61 1,665
Payment of note receivable
officer....................... -- -- -- 75 -- -- --
Net income...................... -- -- -- -- 20,311 -- --
Two-for-one common stock split
effective August 31, 2000
(Note 6)...................... 17,545 176 (176) -- -- -- --
------ ---- ------- ---- ------- ---- -------
BALANCES, SEPTEMBER 30, 1999.... 35,090 $351 $51,249 $ -- $94,803 -- $ --
====== ==== ======= ==== ======= ==== =======
</TABLE>

The accompanying notes are an integral part of these consolidated financial
statements.

F-5
<PAGE> 35

PLEXUS CORP. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS
FOR THE YEARS ENDED SEPTEMBER 30, 1999, 1998 AND 1997
(IN THOUSANDS)

<TABLE>
<CAPTION>
1999 1998 1997
--------- -------- ---------
<S> <C> <C> <C>
CASH FLOWS FROM OPERATING ACTIVITIES
Net income................................................ $ 20,311 $ 22,937 $ 18,893
Adjustments to reconcile net income to net cash flows from
operating activities:
Depreciation and amortization.......................... 9,993 8,372 5,561
Provision for inventories and accounts receivable
allowances........................................... 3,330 4,092 4,911
Deferred income taxes.................................. (1,778) (1,609) (1,049)
Non-operating gains.................................... -- -- (620)
Changes in assets and liabilities:
Accounts receivable.................................. (8,842) (5,547) (15,477)
Inventories.......................................... (25,270) (3,411) (2,376)
Prepaid expenses and other........................... (1,089) (1,283) 230
Accounts payable..................................... 15,569 3,690 7,136
Customer deposits.................................... 1,838 2,466 (5,119)
Accrued liabilities.................................. 869 1,207 6,318
Other................................................ 226 (1,071) (61)
--------- -------- ---------
Cash flows provided by operating activities..... 15,157 29,843 18,347
--------- -------- ---------
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of short-term investments....................... (244,449) (6,632) (7,873)
Sales and maturities of short-term investments............ 232,742 7,319 1,669
Payments for property, plant and equipment................ (18,196) (11,997) (13,488)
Proceeds on sale of property, plant and equipment......... 213 114 724
--------- -------- ---------
Cash flows used in investing activities......... (29,690) (11,196) (18,968)
--------- -------- ---------
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from debt........................................ -- 3,125 96,442
Payments on debt.......................................... (4,561) (4,664) (110,644)
Proceeds from exercise of stock options, including tax
benefit................................................ 8,936 4,217 3,555
Issuances of common stock................................. -- 671 15,212
Treasury stock purchased.................................. (1,160) (3,442) --
Treasury stock reissued................................... 1,091 1,861 --
Payments of preferred stock dividends..................... -- -- (2,103)
--------- -------- ---------
Cash flows provided by financing activities..... 4,306 1,768 2,462
--------- -------- ---------
Net increase (decrease) in cash and cash equivalents........ (10,227) 20,415 1,841
Cash and cash equivalents, beginning of year................ 24,106 3,691 1,850
Effect of SeaMED excluded period............................ 2,027 -- --
--------- -------- ---------
Cash and cash equivalents, end of year...................... $ 15,906 $ 24,106 $ 3,691
========= ======== =========
</TABLE>

The accompanying notes are an integral part of these consolidated financial
statements.

F-6
<PAGE> 36

PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. DESCRIPTION OF BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES

Description of Business: Plexus Corp. provides product realization services
to original equipment manufacturers (OEMs) in the medical, computer (primarily
mainframes, servers and peripherals), industrial, networking, telecommunications
and transportation electronics industries. The Company offers a full range of
services including product development and design services, material procurement
and management, prototyping, manufacturing and assembly, functional and
in-circuit testing, final system box build, distribution and after-market
support.

The contract manufacturing services are provided on either a turnkey basis,
where the Company procures certain or all of the materials required for product
assembly, or on a consignment basis, where the customer supplies materials
necessary for product assembly. Turnkey services include material procurement
and warehousing, in addition to manufacturing, and involve greater resource
investment than consignment services. Turnkey manufacturing currently represents
almost all of the Company's sales.

Consolidation Principles: The consolidated financial statements include the
accounts of Plexus Corp. and its subsidiaries (together "the Company"). All
significant intercompany transactions have been eliminated.

As described more fully in Note 8--"Merger and Acquisition," on July 23,
1999, SeaMED Corporation ("SeaMED"), a public company, was merged into Plexus.
The consolidated financial statements have been prepared following the pooling
of interests method of accounting for the merger and therefore reflect the
combined financial position, operating results and cash flows of the two
companies for all periods presented. SeaMED had a June 30 fiscal year end. Prior
to fiscal 1999, the combined financial statements reflect Plexus' September 30
financial position and results and SeaMED's June 30 financial position and
results. For fiscal 1999, the combined financial statements reflect the October
1, 1998 through September 30, 1999 period for both companies. SeaMED's results
of operations and cash flows from July 1, 1998 to September 30, 1998, which have
been excluded from these consolidated financial statements, are reflected as
adjustments in the 1999 consolidated statements of stockholders' equity and cash
flows. Net sales and net income for SeaMED for the excluded period from July 1,
1998 to September 30, 1998 were $19.4 million and $1.3 million, respectively.

Cash Equivalents and Short-Term Investments: Cash equivalents are highly
liquid investments purchased with an original maturity of less than three
months. Short-term investments are investment-grade short-term debt instruments
with original maturities greater than three months. Short-term investments are
generally comprised of securities with contractual maturities greater than one
year but with optional or early redemption provisions within one year.

Investments in debt securities are classified as "available-for-sale." Such
investments are recorded at fair value as determined from quoted market prices,
and the cost of securities sold is determined on the specific identification
method. If material, unrealized gains or losses are reported as a component of
comprehensive income or losses, net of related tax effect. At September 30,
1999, 1998 and 1997, such unrealized gains and losses were not material. In
addition, there were no realized gains or losses in fiscal 1999, 1998 and 1997.

F-7
<PAGE> 37
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

Short-term investments as of September 30, 1999 and 1998 consist of (in
thousands):

<TABLE>
<CAPTION>
1999 1998
------- ------
<S> <C> <C>
U.S. government and agency securities....................... $ -- $5,517
State and municipal securities.............................. 13,675 --
U.S. corporate and bank debt................................ 8,932 --
Other....................................................... 2,000 --
------- ------
$24,607 $5,517
======= ======
</TABLE>

Approximately $7.4 million and $0 of the total short-term investments as of
September 30, 1999 and 1998, respectively, are included in cash and cash
equivalents.

Inventories: Inventories are valued primarily at the lower of cost or
market. Cost is determined by the first-in, first-out (FIFO) method.

Property, Plant and Equipment and Depreciation: These assets are stated at
cost. Depreciation, determined on the straight-line method, is based on lives
assigned to the major classes of depreciable assets as follows:

<TABLE>
<S> <C>
Buildings and improvements.................................. 18-40 years
Machinery and equipment..................................... 3-10 years
</TABLE>

Revenue Recognition: Revenue is recognized primarily when products are
shipped. Revenue and profit relating to product design and development
contracts, which are short-term in duration, usually less than three months, are
recognized as costs are incurred utilizing the percentage-of-completion method;
any losses are recognized when anticipated. Revenue from design and development
contracts is less than 10% of total revenue in fiscal 1999, 1998, and 1997.
Progress towards completion of product design and development contracts is based
on units of work for labor content and cost for component content.

Income Taxes: Deferred income taxes are provided for differences between
the bases of assets and liabilities for financial and tax reporting purposes.

Earnings Per Share: The computation of basic earnings per common share is
based upon the weighted average number of common shares outstanding and net
income reduced for preferred stock dividends. The computation of diluted
earnings per common share reflects additional dilution from stock options and
convertible preferred shares using the if-converted method.

New Accounting Pronouncements: In March 1998, the American Institute of
Certified Public Accountants ("AICPA") issued Statement of Position ("SOP")
98-1, "Accounting for the Costs of Computer Software Developed or Obtained for
Internal Use", which specifies the accounting treatment of computer software
costs depending upon the type of costs incurred. This SOP is effective for the
Company's fiscal year 2000 financial statements and restatement of prior years
will not be required. The Company does not believe the adoption of this SOP will
have a significant impact on its financial position or results of operations.

Use of Estimates: The preparation of financial statements in conformity
with generally accepted accounting principles requires management to make
estimates and assumptions that affect the amounts reported in the financial
statements and accompanying notes. Actual results could differ from those
estimates.

Fair Value of Financial Instruments: Cash and cash equivalents, short-term
investments, accounts receivable, accounts payable and accrued liabilities are
reflected in the consolidated financial statements at cost because of the
short-term duration of these instruments. The fair value of long-term debt
closely

F-8
<PAGE> 38
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

approximates its carrying value. The Company uses quoted market prices, when
available, or discounted cash flows to calculate these fair values.

Business and Credit Concentrations: Financial instruments that potentially
subject Plexus to concentrations of credit risk consist of cash, cash
equivalents, short-term investments and trade accounts receivable. Plexus' cash,
cash equivalents and short-term investments are managed by recognized financial
institutions which follow the Company's investment policy. Such investment
policy limits the amount of credit exposure in any one issue and the maturity
date of the investment securities that typically comprise investment grade
short-term debt instruments. Concentrations of credit risk in accounts
receivable resulting from sales to major customers are discussed in Note 11.
Plexus at times requires advanced cash deposits for sales. The Company also
closely monitors extensions of credit and has not experienced significant credit
losses in the past.

Reclassifications: Certain amounts in prior years' consolidated financial
statements have been reclassified to conform to the 1999 presentation.

2. INVENTORIES

Inventories as of September 30, 1999 and 1998 consist of (in thousands):

<TABLE>
<CAPTION>
1999 1998
------- -------
<S> <C> <C>
Assembly parts............................................. $40,616 $34,965
Work-in-process............................................ 27,145 21,306
Finished goods............................................. 11,256 1,050
------- -------
$79,017 $57,321
======= =======
</TABLE>

3. PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment as of September 30, 1999 and 1998 consist of
(in thousands):

<TABLE>
<CAPTION>
1999 1998
------- -------
<S> <C> <C>
Land, buildings and improvements........................... $12,009 $10,792
Machinery and equipment.................................... 68,021 51,965
------- -------
80,030 62,757
Less accumulated depreciation............................ 44,162 36,240
------- -------
$35,868 $26,517
======= =======
</TABLE>

4. DEBT

Long-term debt as of September 30, 1999 and 1998 consists of (in
thousands):

<TABLE>
<CAPTION>
1999 1998
---- ------
<S> <C> <C>
Notes and obligations with a weighted average interest rate
of 5.0% and 3.2%, respectively............................ $152 $ 266
Unsecured subordinated note payable, paid in 1999........... -- 493
Variable rate note payable, collateralized by equipment,
paid in 1999.............................................. -- 2,500
---- ------
152 3,259
Less current portion........................................ 10 672
---- ------
$142 $2,587
==== ======
</TABLE>

F-9
<PAGE> 39
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

Revolving Credit Agreement: The Company's revolving credit agreement
provides for maximum borrowings of $40 million with all or a portion of the
principal bearing interest at a LIBOR based or a prime based interest rate as
elected by the Company. These rates are LIBOR plus 0.875% and prime less 0.25%.
The credit agreement is unsecured and a commitment fee of 0.125% per annum on
the unused portion of this agreement is payable quarterly. The agreement matures
in July 2003. The revolving credit agreement, as amended, includes covenants
which require the maintenance of various debt to net worth ratios. There were no
borrowings under this credit agreement at September 30, 1999.

Variable Rate Note Payable: During fiscal 1998, the Company borrowed $2.5
million against a SeaMED equipment credit facility. Borrowings under this
agreement bear interest at LIBOR plus 1.4%. At September 30, 1998, the Company
had an interest rate contract with a notional principal amount of $2.5 million
that effectively converts the variable rate note payable to a fixed rate of
7.5%. This contract was terminated during 1999 in conjunction with the pay down
of the related debt.

Cash paid for interest in fiscal 1999, 1998 and 1997 was $274,000, $87,000,
and $1.2 million, respectively.

5. INCOME TAXES

Income tax expense (benefit) for fiscal 1999, 1998 and 1997 consists of (in
thousands):

<TABLE>
<CAPTION>
1999 1998 1997
------- ------- -------
<S> <C> <C> <C>
Currently payable:
Federal................................................... $14,465 $13,710 $11,332
State..................................................... 3,151 2,244 1,739
------- ------- -------
17,616 15,954 13,071
------- ------- -------
Deferred:
Federal................................................... (1,695) (1,489) (990)
State..................................................... (83) (120) (59)
------- ------- -------
(1,778) (1,609) (1,049)
------- ------- -------
$15,838 $14,345 $12,022
======= ======= =======
</TABLE>

Following is a reconciliation of the Federal statutory income tax rate to
the effective tax rates reflected in the consolidated statements of operations
for fiscal 1999, 1998 and 1997:

<TABLE>
<CAPTION>
1999 1998 1997
---- ---- ----
<S> <C> <C> <C>
Federal statutory income tax rate........................... 35.0% 34.0% 34.0%
Increase (decrease) resulting from:
State income taxes, net of Federal income tax benefit..... 5.7 3.9 3.7
Non-deductible merger costs............................... 3.1 -- --
Other, net................................................ -- 0.6 1.2
---- ---- ----
Effective income tax rate................................. 43.8% 38.5% 38.9%
==== ==== ====
</TABLE>

F-10
<PAGE> 40
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

The components of the net deferred income tax asset as of September 30,
1999 and 1998, consist of (in thousands):

<TABLE>
<CAPTION>
1999 1998
------ ------
<S> <C> <C>
Deferred tax assets:
Inventories............................................... $3,455 $2,448
Accrued benefits.......................................... 1,331 1,450
Loss carryforwards........................................ 156 154
Other..................................................... 2,044 1,296
------ ------
6,986 5,348
Less valuation allowance.................................. (24) (21)
------ ------
6,962 5,327
Deferred tax liabilities:
Property, plant and equipment............................. 807 950
------ ------
Net deferred income tax asset............................... $6,155 $4,377
====== ======
</TABLE>

The Company records a valuation allowance to reflect the estimated amount
of deferred income tax assets which relate to income tax loss carryforwards that
are not expected to be realized.

Cash paid for income taxes in fiscal 1999, 1998 and 1997 was $16.3 million,
$13.0 million and $13.5 million, respectively.

6. STOCKHOLDERS' EQUITY AND SUBSEQUENT EVENT

On August 1, 2000, the Company declared a two-for-one stock split payable
in the form of a stock dividend of one share of common stock for every share of
common stock outstanding. The new stock was issued on August 31, 2000, to
holders of record as of August 22, 2000. Share and per share amounts, where
required, have been restated to reflect this stock split.

On December 19, 1997, the Company's Board of Directors authorized the
repurchase of up to 2,000,000 (pre-split) shares, or a maximum of $25,000,000 of
the Company's common stock on the open market. On March 16, 1999 the Plexus
Corp. Board of Directors rescinded the Company's stock buyback program in
contemplation of the merger with SeaMED.

On July 17, 1997, the Company declared a two-for-one stock split payable in
the form of a stock dividend of one share of common stock for every share of
common stock outstanding. The new stock was issued on August 25, 1997 to holders
of record as of August 14, 1997. Share and per share amounts, where required,
have been restated to reflect this stock split.

On February 28, 1997, the holders of the 7,000 shares of issued and
outstanding Plexus Corp. Series A Preferred Shares converted all such shares, in
accordance with their terms, into a total of 554,454 (pre-splits) shares of the
Company's common stock. In November 1996, the Class A, B, C and D convertible
redeemable preferred stock of SeaMED was converted into a total of 586,806
(pre-splits) shares of the Company's common stock. Also issued was a warrant to
purchase 15,626 (pre-splits) shares of common stock. The warrant was exercised
in March 1998 in a non-cash transaction which resulted in the issuance of 11,158
(pre-split) shares.

In November 1996, SeaMED completed an initial public offering of 305,944
(pre-splits) shares of common stock. Net proceeds were $14.8 million (net of
offering costs and underwriters discount of $2.0 million). SeaMED used $1.8
million of the proceeds to pay previously undeclared cumulative dividends on its
Class A and D convertible redeemable preferred stock.

F-11
<PAGE> 41
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

Income tax benefits attributable to stock options exercised are recorded as
an increase in additional paid-in capital.

7. EARNINGS PER SHARE

The following is a reconciliation of the amounts utilized in the
computation of basic and diluted earnings per share (in thousands except per
share amounts):

<TABLE>
<CAPTION>
SEPTEMBER 30,
-----------------------------
1999 1998 1997
------- ------- -------
<S> <C> <C> <C>
BASIC EARNINGS PER SHARE (NOTE 6):
Net income................................................ $20,311 $22,937 $18,893
Less: Preferred stock dividends........................... -- -- 312
------- ------- -------
Income available to common stockholders................... $20,311 $22,937 $18,581
======= ======= =======
Basic weighted average shares outstanding................. 34,646 33,688 30,732
======= ======= =======
BASIC EARNINGS PER SHARE.................................... $ 0.59 $ 0.68 $ 0.60
======= ======= =======
DILUTED EARNINGS PER SHARE (NOTE 6):
Net income................................................ $20,311 $22,937 $18,893
======= ======= =======
Weighted average shares outstanding....................... 34,646 33,688 30,732
Effect of dilutive securities:
Stock options........................................ 2,375 2,490 2,538
Stock warrants....................................... -- 18 18
Convertible preferred stock.......................... -- -- 1,828
------- ------- -------
Diluted weighted average shares outstanding............ 37,021 36,196 35,116
======= ======= =======
DILUTED EARNINGS PER SHARE.................................. $ 0.55 $ 0.63 $ 0.54
======= ======= =======
</TABLE>

8. MERGER AND ACQUISITION

Merger: In July 1999, Plexus acquired SeaMED. Pursuant to the merger
agreement, SeaMED stockholders received 0.40 of a share of Plexus common stock
(pre-split) for each share of SeaMED common stock. Plexus issued approximately
2.27 million shares of its common stock (pre-split) in exchange for all
outstanding common stock of SeaMED. SeaMED stock options outstanding, as of the
merger date, were exchanged for options to acquire approximately 171,764 shares
of Plexus common stock (pre-split) at the same time. SeaMED is a provider of
engineering and manufacturing services, coupled with regulatory expertise, of
advanced medical instruments for medical technology companies. All merger costs
and other one-time expenses related to the SeaMED merger have been expensed as
required under the pooling of interests method of accounting. Certain
merger-related costs, which included charges related to obsolete inventories and
a loss on an engineering contract, have been included in cost of sales in the
consolidated statement of operations. All such costs and expenses amounted to
$6.0 million after income taxes in fiscal 1999 and are reflected in the
financial statements as follows (in thousands):

<TABLE>
<S> <C>
Cost of sales............................................... $2,177
Plant closing, relocation and severance..................... 981
Merger costs................................................ 4,557
------
7,715
Less: income tax benefit.................................... 1,684
------
Net merger and other one-time charges....................... $6,031
======
</TABLE>

F-12
<PAGE> 42
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

The results of operations previously reported by the separate companies and
the combined amounts presented in the accompanying consolidated financial
statements are reconciled below (in thousands):

<TABLE>
<CAPTION>
SEPTEMBER 30,
NINE MONTHS ENDED --------------------
JUNE 30, 1999 1998 1997
----------------- -------- --------
(UNAUDITED)
<S> <C> <C> <C>
Net sales:
Plexus................................................ $310,717 $396,815 $386,431
SeaMED................................................ 49,463 69,980 52,134
-------- -------- --------
Combined.............................................. $360,180 $466,795 $438,565
======== ======== ========
Net income:
Plexus................................................ $ 18,228 $ 19,235 $ 16,400
-------- -------- --------
SeaMED:
As previously reported............................. (1,813) 4,139 2,726
Conforming accounting adjustments.................. 401 (437) (233)
-------- -------- --------
Restated......................................... (1,412) 3,702 2,493
-------- -------- --------
Combined......................................... $ 16,816 $ 22,937 $ 18,893
======== ======== ========
</TABLE>

The adjustments above conform SeaMED's method of accounting for inventory
with that of Plexus, net of related tax effect.

Acquisition: On September 1, 1999, Plexus Corp. purchased certain printed
circuit board assembly manufacturing assets from an unrelated party. The
manufacturing assets which consisted principally of equipment and inventories
were purchased at approximately fair market value. The Company also leases a
portion of a manufacturing facility owned by the unrelated party which houses
the printed circuit board operations. The Company has agreed to acquire certain
other assets from the same unrelated party in fiscal 2000. The total purchase
price of the net assets acquired in fiscal 1999 and to be acquired in fiscal
2000 is not material to the assets or stockholders' equity of the Company. Pro
forma statements of operations for fiscal 1999 and 1998 reflecting this
acquisition are not shown as they would not differ materially from the reported
results.

9. LEASE COMMITMENTS

The Company has a number of operating lease agreements primarily involving
manufacturing facilities, manufacturing equipment and computerized design
equipment. These leases are non-cancelable and expire on various dates through
2014. Rent expense under all operating leases for fiscal 1999, 1998 and 1997 was
approximately $11.3 million, $10.2 million and $11.5 million, respectively.
Renewal and purchase options are available on certain of these leases. The sale
of equipment obtained through the exercise of the purchase option on certain
leases resulted in miscellaneous income of $620,000 in fiscal 1997.

In April 1997, the Company began leasing a new 110,000-square-foot
manufacturing facility located in Green Bay, Wisconsin. The facility was
constructed and equipped by Oneida Nation Electronics (ONE), a corporation
chartered by the Oneida Tribe of Indians of Wisconsin. All lease payments for
the building and equipment are based on the profitability of the facility
pursuant to a formula defined in the lease agreement. There are no required
minimum lease payments.

F-13
<PAGE> 43
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

Future minimum annual payments on operating leases are as follows (in
thousands):

<TABLE>
<S> <C>
2000................... $ 8,437
2001................... 5,632
2002................... 5,037
2003................... 5,001
2004................... 4,823
Thereafter............. 19,702
-------
$48,632
=======
</TABLE>

10. BENEFIT PLANS

401(k) Savings Plans: The Company's 401(k) savings plans cover
substantially all eligible employees. The Company matches employee
contributions, based on years of service, up to 2.5% of eligible earnings. The
Company's contributions for fiscal 1999, 1998 and 1997 totaled $1.6 million,
$1.4 million and $1.2 million, respectively.

Stock Option Plans: The Company has reserved 12.0 million shares of common
stock for grant to officers and key employees under an employee stock option
plan, of which 8.2 million shares have been granted. The exercise price of each
option granted shall not be less than the fair market value on the date of grant
and options vest over a three year period from date of grant. The plan also
authorizes the Company to grant 600,000 stock appreciation rights, none of which
have been granted.

In connection with the SeaMED merger occurring in fiscal 1999 (see Note
8--"Merger and Acquisition"), all of the options outstanding under the former
SeaMED stock option plans were assumed by the Company and converted into options
to purchase shares of the Company's Common Stock on terms adjusted to reflect
the Merger exchange ratio. Options to acquire a total of 429,410 SeaMED shares
were converted into options to acquire a total of 171,764 Plexus shares
(pre-split). The SeaMED stock option plans are similar to the Plexus plans above
and options vest over a four year period from date of grant. These plans have
been terminated; however, the outstanding options, as so adjusted, retain all of
the rights, terms and conditions of the respective plans under which they were
originally granted until their expiration.

Under a separate plan, each independent outside director is granted 1,500
stock options each December 1, with option pricing similar to the employee
plans. These options are fully vested upon grant and can be exercised after a
minimum six-month holding period. The 400,000 shares of common stock authorized
under this plan may come from any combination of authorized but unissued shares,
treasury stock or the open market.

F-14
<PAGE> 44
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

A summary of the stock option activity follows:

<TABLE>
<CAPTION>
SHARES WEIGHTED AVERAGE
(IN THOUSANDS) EXERCISE PRICE
-------------- ----------------
<S> <C> <C>
Options outstanding at October 1, 1996............ 4,478 $ 3.07
Granted........................................... 1,396 $ 6.92
Canceled.......................................... (68) $ 3.35
Exercised......................................... (1,334) $ 2.68
------
OPTIONS OUTSTANDING AT SEPTEMBER 30, 1997......... 4,472 $ 4.38
Granted........................................... 812 $11.80
Canceled.......................................... (86) $ 6.13
Exercised......................................... (562) $ 3.08
------
OPTIONS OUTSTANDING AT SEPTEMBER 30, 1998......... 4,636 $ 5.81
Effect of SeaMED excluded period.................. 62 $23.35
Granted........................................... 980 $15.29
Canceled.......................................... (164) $16.21
Exercised......................................... (1,092) $ 3.81
------
OPTIONS OUTSTANDING AT SEPTEMBER 30, 1999......... 4,422 $ 8.26
======
OPTIONS EXERCISABLE AT:
September 30, 1997.............................. 1,914 $ 3.01
====== ======
September 30, 1998.............................. 2,500 $ 3.70
====== ======
September 30, 1999.............................. 2,518 $ 5.21
====== ======
</TABLE>

The following table summarizes outstanding stock option information at
September 30, 1999 (shares in thousands):

<TABLE>
<CAPTION>
RANGE OF NUMBER WEIGHTED AVERAGE WEIGHTED AVERAGE NUMBER WEIGHTED AVERAGE
EXERCISE PRICES OUTSTANDING EXERCISE PRICE REMAINING LIFE EXERCISABLE EXERCISE PRICE
--------------- ----------- ---------------- ---------------- ----------- ----------------
<S> <C> <C> <C> <C> <C>
$ 0.63 - $ 3.75 1,408 $ 3.07 5.6 years 1,400 $ 3.07
$ 4.15 - $ 6.25 1,210 $ 5.91 6.8 years 794 $ 5.78
$ 9.25 - $14.50 730 $10.67 8.3 years 242 $10.69
$14.75 - $22.50 1,074 $16.09 8.8 years 82 $20.15
$ 0.63 - $22.50 4,422 $ 8.26 7.2 YEARS 2,518 $ 5.21
</TABLE>

The Company has elected to account for its stock option plans under the
guidelines of Accounting Principles Board Opinion No. 25. Accordingly, no
compensation cost related to the stock option plans has been recognized in the
consolidated statements of operations. Had the Company recognized compensation
expense based on the fair value at the grant date for awards under the plans,
the Company's net income for fiscal 1999, 1998 and 1997 would have been reduced
by approximately $2.8 million, $2.9 million and $1.5 million, respectively.
Basic earnings per share would have been reduced by $0.08, $0.09 and $0.05 in
fiscal 1999, 1998 and 1997, respectively. These pro forma results will not be
representative of the impact in future years because only grants made since
October 1, 1995 were considered.

The weighted average fair value of options granted per share during fiscal
1999, 1998 and 1997 is $8.41, $6.61, $3.31, respectively. The fair value of each
option grant is estimated at the date of grant using the Black-Scholes prorated
straight line option-pricing method with the following assumption ranges: 45% to
61% volatility, risk free interest rates ranging from 4.1% to 6.6%, expected
option life of 4.5 to 6.0 years, and no expected dividends.

F-15
<PAGE> 45
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

Deferred Compensation Plan: In September 1996, the Company entered into
agreements with certain of its officers under a nonqualified deferred
compensation plan. Under the plan, the Company has agreed to pay certain amounts
annually for the first 15 years subsequent to retirement or to a designated
beneficiary upon death. It is management's intent that life insurance contracts
owned by the Company will fund this plan. Expense for this plan totaled
$361,000, $343,000 and $315,000 in fiscal 1999, 1998, and 1997, respectively.

Other: The Company is not obligated to provide any post-retirement medical
or life insurance benefits to employees.

11. BUSINESS SEGMENT AND MAJOR CUSTOMERS

The Company adopted Statement of Financial Accounting Standards ("SFAS")
No. 131, "Disclosure about Segments of an Enterprise and Related Information" in
fiscal 1999. SFAS No. 131 establishes standards for the way public business
enterprises are to report information about operating segments in annual
financial reports issued to shareholders. It also establishes standards for
related disclosures about products and services, geographic area and major
customers.

The Company and its subsidiaries operate in one business segment, the
production and sale of electronic products including the designing,
manufacturing, programming and testing of computerized electronic assemblies.
Additionally all of the Company's operations are located in the United States.

The following table summarizes the percentage of net sales to customers
that account for more than 10% of net sales in fiscal 1999, 1998 and 1997:

<TABLE>
<CAPTION>
1999 1998 1997
---- ---- ----
<S> <C> <C> <C>
Lucent Technologies Inc................................ 16% * *
General Electric Company............................... 12% * 11%
International Business Machines Corporation............ * * 10%
</TABLE>

(* represents sales less than 10%)

Accounts receivable related to Lucent and General Electric represent 14%
and 7%, respectively, of the Company's trade accounts receivable as of September
30, 1999.

F-16
<PAGE> 46
PLEXUS CORP. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--CONTINUED

12. QUARTERLY FINANCIAL DATA (UNAUDITED)

Summarized quarterly financial data for fiscal 1999 and 1998 consists of
(in thousands, except per share amounts):

<TABLE>
<CAPTION>
FIRST SECOND THIRD FOURTH
1999 QUARTER QUARTER QUARTER QUARTER TOTAL
---- -------- -------- -------- -------- --------
<S> <C> <C> <C> <C> <C>
Net sales................................. $120,585 $119,165 $120,430 $132,234 $492,414
Gross profit.............................. 16,904 16,828 13,714 18,963 66,409
Net income................................ 6,825 6,265 3,726 3,495 20,311
Earnings per share
Basic................................... $ 0.20 $ 0.18 $ 0.11 $ 0.10 $ 0.59
Diluted................................. $ 0.19 $ 0.17 $ 0.10 $ 0.09 $ 0.55
</TABLE>

<TABLE>
<CAPTION>
FIRST SECOND THIRD FOURTH
1998 QUARTER QUARTER QUARTER QUARTER TOTAL
---- -------- -------- -------- -------- --------
<S> <C> <C> <C> <C> <C>
Net sales................................. $111,935 $113,948 $116,827 $124,085 $466,795
Gross profit.............................. 12,426 14,104 15,870 17,747 60,147
Net income................................ 4,462 5,128 6,207 7,140 22,937
Earnings per share
Basic................................... $ 0.13 $ 0.15 $ 0.18 $ 0.21 $ 0.68
Diluted................................. $ 0.12 $ 0.14 $ 0.17 $ 0.20 $ 0.63
</TABLE>

Earnings per share is computed independently for each quarter. The annual
per share amount may not equal the sum of the quarterly amounts due to rounding.

F-17
<PAGE> 47

PROSPECTUS

$500,000,000

[PLEXUS LOGO]
55 JEWELERS PARK DRIVE
NEENAH, WISCONSIN 54957-0156
(920) 722-3451

DEBT SECURITIES
COMMON STOCK
(WITH ATTACHED PREFERRED STOCK PURCHASE RIGHTS)

When we offer securities, we will provide you with a prospectus supplement
describing the terms of the specific issue of securities, including the offering
price of the securities. The prospectus supplement may also add, update or
change information contained in this prospectus. You should read this prospectus
and any supplements carefully before you invest.

Plexus Corp. may offer from time to time:

- unsecured debt securities consisting of debentures, notes and/or other
evidences of unsecured indebtedness in one or more series

- common stock, par value $.01 per share (with attached preferred stock
purchase rights)

- any combination of the foregoing, at an aggregate initial offering price
not to exceed $500,000,000, at prices and on terms to be determined at or
prior to the time of sale in light of market conditions at the time of
sale.

Plexus common stock is quoted on the Nasdaq National Market, under the
symbol "PLXS." On August 31, 2000, the last reported sale price for the common
stock was $77.38 per share.

We urge you to read this prospectus and the accompanying prospectus
supplement carefully before you make your investment decision. INVESTING IN OUR
SECURITIES INVOLVES RISKS. SEE "RISK FACTORS" BEGINNING ON PAGE 2.

---------------------------

THE SECURITIES AND EXCHANGE COMMISSION AND STATE SECURITIES REGULATORS
HAVE NOT APPROVED OR DISAPPROVED THESE SECURITIES OR DETERMINED IF THIS
PROSPECTUS IS TRUTHFUL AND COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.

---------------------------

THE DATE OF THIS PROSPECTUS IS SEPTEMBER 15, 2000.

<PAGE> 48

TABLE OF CONTENTS

<TABLE>
<CAPTION>
PAGE
----
<S> <C>
About This Prospectus....................................... 1
The Company................................................. 1
Forward-Looking Statements and Cautionary Factors........... 1
Risk Factors................................................ 2
Where You Can Find More Information......................... 9
Use of Proceeds............................................. 11
Ratio of Earnings to Fixed Charges.......................... 11
Description of Debt Securities.............................. 11
Description of Capital Stock................................ 16
Book-Entry.................................................. 19
Plan of Distribution........................................ 21
Certain Legal Matters....................................... 22
Experts..................................................... 22
</TABLE>

------------------------------

We have not authorized anyone to give any information or to make any
representation not contained or incorporated by reference in this prospectus or
the accompanying prospectus supplement. You should not rely upon any other
information or representation as having been authorized by us or any
underwriter, dealer or agent. Plexus does not imply or represent by delivering
this prospectus that Plexus, or its business, is unchanged after the date of the
prospectus or that the information herein is correct as of any time after that
date.

The information in this prospectus or any supplement may not contain all of
the information that may be important to you. You should read the entire
prospectus or any supplement, as well as the documents incorporated by reference
in the prospectus or any supplement, before making an investment decision.
<PAGE> 49

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we
filed with the Securities and Exchange Commission utilizing a "shelf"
registration process. Using this process, we may, from time to time, offer any
combination of securities described in this prospectus in one or more offerings
with a total initial offering price of up to $500,000,000. This prospectus
provides you with a general description of the securities we may offer. Each
time we sell securities, we will provide a prospectus supplement and any pricing
supplement that will contain specific information about the terms of that
particular offering. The prospectus supplement or pricing supplement may also
add, update or change information contained in this prospectus. To obtain
additional information that may be important to you, you should read the
exhibits. You should read both this prospectus and any applicable prospectus
supplement together with the additional information described under the heading
"Where You Can Find More Information."

When used in this prospectus and any prospectus supplement, the terms
"Plexus," "we," "our," "us" and the "Company" refer to Plexus Corp. and its
subsidiaries.

Unless we note otherwise, all share and per share information has been
adjusted to give effect to the two-for-one stock splits effective August 25,
1997 and August 31, 2000.

THE COMPANY

Plexus provides design, manufacturing and testing services to the
electronics industry. Through our wholly owned subsidiaries, we provide product
realization services to original equipment manufacturers in the
networking/telecommunications, medical, industrial, computer and transportation
industries. We offer a full range of services including product development and
design, new product introduction, material procurement and management,
prototyping, assembly, testing, manufacturing and after-market support.

Our headquarters and largest operations are located in Neenah, Wisconsin.
Our other U.S. operations are located in California, Colorado, Illinois,
Kentucky, Massachusetts, Minnesota, North Carolina and Washington. In addition,
we have recently acquired foreign operations in Juarez, Mexico, Kelso, Scotland
and Maldon, England. We continue to look for opportunities for technical
capabilities and geographic expansion that will improve our ability to provide
services to our customers.

FORWARD-LOOKING STATEMENTS AND CAUTIONARY FACTORS

This prospectus and any prospectus supplement, including the documents
incorporated by reference, may contain statements that constitute
forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995. Prospective investors are cautioned that any such
forward-looking statements are not guarantees of future performance and involve
known and unknown risks, uncertainties and other factors which may cause the
actual results, performance or achievements to differ materially from the future
results, performance or achievements expressed or implied in the forward-
looking statements. The words "anticipate," "believe," "estimate," "expect,"
"project," "objective" and similar expressions are intended to identify
forward-looking statements. In addition to the assumptions and other factors
referred to specifically in connection with those statements, factors that could
cause our actual results to differ materially from those contemplated in the
forward-looking statements include factors described under the caption "Risk
Factors" or similar cautionary captions in the documents incorporated herein by
reference.

1
<PAGE> 50

RISK FACTORS

Any investment in the securities we are offering involves significant risk.
You should consider carefully the following information about these risks,
together with the other information contained or incorporated by reference into
this prospectus or in any supplement to this prospectus, before you decide to
buy our securities. If any of the following risks actually occur, our business,
operating results and financial condition would suffer, possibly to a material
degree. In these circumstances, the market price of our securities could
decline, and you may lose part or all of the money you paid to buy our
securities. You may obtain the information incorporated by reference into this
prospectus without charge by following the instructions in the "Where You Can
Find More Information" section of this prospectus.

OUR CUSTOMER REQUIREMENTS AND OPERATING RESULTS VARY SIGNIFICANTLY FROM QUARTER
TO QUARTER, WHICH COULD NEGATIVELY IMPACT THE PRICE OF OUR COMMON STOCK.

Our quarterly results may vary significantly depending on various factors,
many of which are beyond our control. These factors include:

- the volume of customer orders relative to our capacity

- the timing of customer orders, particularly in light of the fact that
some of our customers place a significant percentage of their orders
during the last few weeks of a quarter

- the typical short life cycle of our customers' products

- market acceptance of and demand for our customers' products

- changes in our sales mix to our customers

- the timing of our expenditures in anticipation of future orders

- our effectiveness in managing manufacturing processes

- changes in cost and availability of labor and components

- changes in economic conditions

- local events that may affect our production volume, such as local
holidays.

Due to the nature of turnkey manufacturing services, our quarterly and
annual results are affected by the level and timing of customer orders,
fluctuations in material costs and availability, and the degree of automation
used in the manufacturing process.

OUR CUSTOMERS MAY CANCEL THEIR ORDERS, CHANGE PRODUCTION QUANTITIES OR DELAY
PRODUCTION.

Electronics manufacturing service providers must provide increasingly rapid
product turnaround for their customers. We generally do not obtain firm,
long-term purchase commitments from our customers and we continue to experience
reduced lead-times in customer orders. Customers may cancel their orders, change
production quantities or delay production for a number of reasons. The success
of our customers' products in the market affects our business. Cancellations,
reductions or delays by a significant customer or by a group of customers could
seriously harm our operating results.

In addition, we make significant decisions, including determining the
levels of business that we will seek and accept, production schedules, component
procurement commitments, personnel needs and other resource requirements, based
on our estimates of customer requirements. The short-term nature of our
customers' commitments and the possibility of rapid changes in demand for their
products reduces our ability to estimate accurately the future requirements of
those customers.

On occasion, customers may require rapid increases in production, which can
stress our resources and reduce operating margins. Although we have increased
our manufacturing capacity and plan further increases, we may not have
sufficient capacity at any given time to meet all of our customers' demands. In

2
<PAGE> 51

addition, because many of our costs and operating expenses are relatively fixed,
a reduction in customer demand can harm our gross margins and operating results.

WE MAY NOT BE ABLE TO OBTAIN RAW MATERIALS OR COMPONENTS FOR OUR ASSEMBLIES ON A
TIMELY BASIS OR AT ALL.

We rely on a limited number of suppliers for many components used in the
assembly process. We do not have any long-term supply agreements. At various
times, there have been shortages of some of the electronic components that we
use, and suppliers of some components have lacked sufficient capacity to meet
the demand for these components. Over the past 12-plus months, component
shortages have become more prevalent in our industry. In some cases, supply
shortages and delays in deliveries of particular components have resulted in
curtailed production, or delays in production, of assemblies using that
component, which has contributed to an increase in our inventory levels. We
expect that shortages and delays in deliveries of some components will continue.
If we are unable to obtain sufficient components on a timely basis, we may
experience manufacturing and shipping delays, which could harm our relationships
with customers and reduce our sales.

A significant portion of our sales is derived from turnkey manufacturing in
which we provide materials procurement. While most of our customer contracts
permit quarterly or other periodic adjustments to pricing based on decreases and
increases in component prices and other factors, we typically bear the risk of
component price increases that occur between any such repricings or, if such
repricing is not permitted, during the balance of the term of the particular
customer contract. Accordingly, component price increases could adversely affect
our operating results.

THE MAJORITY OF OUR SALES COMES FROM A SMALL NUMBER OF CUSTOMERS AND IF WE LOSE
ANY OF THESE CUSTOMERS, OUR SALES AND OPERATING RESULTS COULD DECLINE
SIGNIFICANTLY.

Sales to our ten largest customers have represented a majority of our sales
in recent periods. Our ten largest customers accounted for approximately 67% of
our net sales for the nine months ended June 30, 2000 and 61% of our fiscal 1999
net sales. Our largest customers were Lucent Technologies and General Electric
accounting for approximately 24% and 11%, respectively, of our net sales for the
nine month period ended June 30, 2000 and 16% and 12%, respectively, of our
fiscal 1999 net sales. The identities of our principal customers have varied
from year to year, and our principal customers may not continue to purchase
services from us at current levels, if at all. Significant reductions in sales
to any of these customers, or the loss of major customers, could seriously harm
our business. If we are not able to timely replace expired, canceled or reduced
contracts with new business, our sales will decrease.

WE MAY FAIL TO COMPLETE SUCCESSFULLY FUTURE ACQUISITIONS AND MAY NOT INTEGRATE
SUCCESSFULLY ACQUIRED BUSINESSES, WHICH COULD ADVERSELY AFFECT OUR OPERATING
RESULTS.

We have pursued a strategy that has included growth through acquisitions.
We cannot assure you that we will be able to complete successfully future
acquisitions, due primarily to increased competition for the acquisition of
electronics manufacturing service operations. If we are unable to acquire
additional businesses, our growth could be inhibited. Similarly, we cannot
assure you that we will be able to integrate successfully the operations and
management of our recent acquisitions or future acquisitions. Acquisitions
involve significant risks that could have a material adverse effect on us. These
risks include:

OPERATING RISKS, SUCH AS THE:

- inability to integrate successfully our acquired operations, businesses
and personnel

- inability to realize anticipated synergies, economies of scale or other
value

- difficulties in scaling up production and coordinating management of
operations at new sites

- strain placed on our personnel, systems and resources

3
<PAGE> 52

- possible modification or termination of an acquired business customer
program, including cancellation of current or anticipated programs

- loss of key employees of acquired businesses.

FINANCIAL RISKS, SUCH AS THE:

- dilutive effect of the issuance of additional equity securities

- incurrence of additional debt and related interest costs

- inability to achieve expected operating margins to offset the increased
fixed costs associated with acquisitions

- incurrence of large write-offs or write-downs

- amortization of goodwill or other intangible assets

- unforeseen liabilities of the acquired businesses.

EXPANSION OF OUR BUSINESS AND OPERATIONS MAY NEGATIVELY IMPACT OUR BUSINESS.

We may expand our operations by establishing or acquiring new facilities or
by expanding capacity in our current facilities. We may expand both in
geographical areas in which we currently operate and in new geographical areas
within the United States and internationally. We may not be able to find
suitable facilities on a timely basis or on terms satisfactory to us. Expansion
of our business and operations involves numerous business risks, including the:

- inability to integrate successfully additional facilities or capacity and
to realize anticipated synergies, economies of scale or other value

- additional fixed costs which may not be fully absorbed by the new
business

- difficulties in the timing of expansions, including delays in the
implementation of construction and manufacturing plans

- diversion of management's attention from other business areas during the
planning and implementation of expansions

- strain placed on our operational, financial, management, technical and
information systems and resources

- disruption in manufacturing operations

- incurrence of significant costs and expenses

- inability to locate enough customers or employees to support the
expansion.

OPERATING IN FOREIGN COUNTRIES EXPOSES US TO INCREASED RISKS.

We recently acquired operations in Mexico and the United Kingdom as a
result of purchasing the turnkey contract electronics manufacturing service
operations of Elamex, S.A. de C.V. and the stock of Keltek (Holdings) Limited.
We may in the future expand into other international regions. We have limited
experience in managing geographically dispersed operations and in operating in
Mexico and the United Kingdom. We also purchase a significant number of
components manufactured in foreign countries. Because of these international
aspects of our operations, we are subject to the following risks that could
materially impact our operating results:

- economic or political instability

- transportation delays or interruptions and other effects of less
developed infrastructure in many countries

4
<PAGE> 53

- foreign exchange rate fluctuations

- utilization of different systems and equipment

- difficulties in staffing and managing foreign personnel and diverse
cultures.

In addition, changes in policies by the U.S. or foreign governments could
negatively affect our operating results due to changes in duties, tariffs, taxes
or limitations on currency or fund transfers. Also, our Mexico based operation
utilizes the Maquiladora program, which provides reduced tariffs and eases
import regulations, and we could be adversely affected by changes in that
program.

WE MAY NOT BE ABLE TO MAINTAIN OUR ENGINEERING, TECHNOLOGICAL AND MANUFACTURING
PROCESS EXPERTISE.

The markets for our manufacturing and engineering services are
characterized by rapidly changing technology and evolving process development.
The continued success of our business will depend upon our ability to:

- hire, retain and expand our qualified engineering and technical personnel

- maintain and enhance our technological capabilities

- develop and market manufacturing services which meet changing customer
needs

- successfully anticipate or respond to technological changes in
manufacturing processes on a cost-effective and timely basis.

Although we believe that our operations utilize the assembly and testing
technologies, equipment and processes that are currently required by our
customers, we cannot be certain that we will develop the capabilities required
by our customers in the future. The emergence of new technologies, industry
standards or customer requirements may render our equipment, inventory or
processes obsolete or noncompetitive. In addition, we may have to acquire new
assembly and testing technologies and equipment to remain competitive. The
acquisition and implementation of new technologies and equipment may require
significant expense or capital investment which could reduce our operating
margins and our operating results. Our failure to anticipate and adapt to our
customers' changing technological needs and requirements could have an adverse
effect on our business.

FAILURE TO MANAGE OUR GROWTH MAY SERIOUSLY HARM OUR BUSINESS.

We have experienced rapid growth, both internally and through acquisitions.
This growth has placed, and will continue to place, significant strain on our
operations. To manage our growth effectively, we must continue to improve and
expand our financial, operational and management information systems; continue
to develop the management skills of our managers and supervisors; and continue
to train, manage and motivate our employees. If we are unable to manage our
growth effectively, our operating results could be harmed.

OUR TURNKEY MANUFACTURING SERVICES INVOLVE INVENTORY RISK.

Some of our contract manufacturing services are provided on a turnkey
basis, where we purchase some or all of the materials required for designing,
product assembling and manufacturing. These services involve greater resource
investment and inventory risk management than consignment services, where the
customer provides these materials. Accordingly, various component price
increases and inventory obsolescence could adversely affect our selling price,
gross margins and operating results.

START-UP COSTS AND INEFFICIENCIES RELATED TO NEW PROGRAMS CAN ADVERSELY AFFECT
OUR OPERATING RESULTS.

Start-up costs, the management of labor and equipment resources in
connection with the establishment of new programs and new customer
relationships, and the need to estimate required resources in advance can
adversely affect our gross margins and operating results. These factors are
particularly evident in the early stages of the life-cycle of new products and
new programs. These factors
5
<PAGE> 54

also affect our ability to efficiently use labor and equipment. In addition, if
any of these new programs or new customer relationships were terminated, our
operating results could be harmed, particularly in the short-term.

WE ARE SUBJECT TO EXTENSIVE GOVERNMENT REGULATIONS.

We are also subject to environmental regulations relating to the use,
storage, discharge, recycling and disposal of hazardous chemicals used in our
manufacturing process. If we fail to comply with present and future regulations,
we could be subject to future liabilities or the suspension of business. These
regulations could restrict our ability to expand our facilities or require us to
acquire costly equipment or incur significant expense. While we are not
currently aware of any material violations, we may have to spend funds to comply
with present and future regulations or be required to perform site remediation.

In addition, our medical device business, which represented approximately
31% of our fiscal year 1999 sales, is subject to substantial government
regulation, primarily from the FDA and similar regulatory bodies in other
countries. We must comply with statutes and regulations covering the design,
development, testing, manufacturing, labeling, marketing and distribution of
medical devices and the reporting of certain information regarding their safety.
Noncompliance with these rules can result in, among other things, us and our
customers being subject to fines, injunctions, civil penalties, criminal
prosecution, recall or seizure of devices, total or partial suspension of
production, failure of the government to grant pre-market clearance or record
approvals for projections or the withdrawal of marketing approvals. The FDA also
has the authority to require repair or replacement of equipment, or refund of
the cost of a device manufactured or distributed by our customers. In addition,
the failure or noncompliance could have an adverse effect on our reputation.

OUR PRODUCTS ARE FOR THE ELECTRONICS INDUSTRY, WHICH PRODUCES TECHNOLOGICALLY
ADVANCED PRODUCTS WITH SHORT LIFE CYCLES.

Factors affecting the electronics industry, in particular the short life
cycle of products, could seriously harm our customers and, as a result, us.
These factors include:

- the inability of our customers to adapt to rapidly changing technology
and evolving industry standards, which result in short product life
cycles

- the inability of our customers to develop and market their products, some
of which are new and untested

- the potential that our customers' products may become obsolete or the
failure of our customers' products to gain widespread commercial
acceptance.

INCREASED COMPETITION MAY RESULT IN DECREASED DEMAND OR PRICES FOR OUR SERVICES.

The electronics manufacturing services industry is highly competitive. We
compete against numerous U.S. and foreign electronics manufacturing services
providers with global operations, as well as those who operate on a local or
regional basis. In addition, current and prospective customers continually
evaluate the merits of manufacturing products internally. Consolidation in the
electronics manufacturing services industry results in a continually changing
competitive landscape. The consolidation trend in the industry also results in
larger and more geographically diverse competitors who have significant combined
resources with which to compete against us.

Some of our competitors have substantially greater managerial,
manufacturing, engineering, technical, financial, systems, sales and marketing
resources than we do. These competitors may:

- respond more quickly to new or emerging technologies

- have greater name recognition, critical mass and geographic and market
presence

- be better able to take advantage of acquisition opportunities

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<PAGE> 55

- adapt more quickly to changes in customer requirements

- devote greater resources to the development, promotion and sale of their
services

- be better positioned to compete on price for their services.

We may be operating at a cost disadvantage compared to manufacturers who
have greater direct buying power from component suppliers, distributors and raw
material suppliers or who have lower cost structures. As a result, competitors
may procure a competitive advantage and obtain business from our customers. Our
manufacturing processes are generally not subject to significant proprietary
protection, and companies with greater resources or a greater market presence
may enter our market or increase their competition with us. Increased
competition could result in price reductions, reduced sales and margins or loss
of market share.

WE MAY FAIL TO SECURE NECESSARY ADDITIONAL FINANCING.

We have made and intend to continue to make substantial capital
expenditures to expand our operations, acquire businesses and remain competitive
in the rapidly changing electronics manufacturing services industry. Our future
success may depend on our ability to obtain additional financing and capital to
support our continued growth and operations, including our working capital
needs. We may seek to raise capital by:

- issuing additional common stock or other equity securities

- issuing debt securities

- increasing available borrowings under our existing credit facility or
obtaining new credit facilities

- obtaining off-balance sheet financing.

We may not be able to obtain additional capital when we want or need it,
and capital may not be available on satisfactory terms. If we issue additional
equity securities or convertible debt to raise capital, it may be dilutive to
your ownership interest. Furthermore, any additional financing and capital may
have terms and conditions that adversely affect our business, such as
restrictive financial or operating covenants.

WE DEPEND ON CERTAIN KEY PERSONNEL, AND THE LOSS OF KEY PERSONNEL MAY HARM OUR
BUSINESS.

Our future success depends in large part on the continued service of our
key technical and management personnel and on our ability to continue to attract
and retain qualified employees, particularly those highly skilled design,
process and test engineers involved in the manufacture of existing products and
the development of new products and processes. The competition for these
individuals is intense, and the loss of key employees, generally none of whom is
subject to an employment agreement for a specified term or a post-employment
non-competition agreement, could harm our business. We believe that we have a
relatively small management group whose resources could be strained as a result
of expansion of our business.

PRODUCTS WE MANUFACTURE MAY CONTAIN DESIGN OR MANUFACTURING DEFECTS WHICH COULD
RESULT IN REDUCED DEMAND FOR OUR SERVICES AND LIABILITY CLAIMS AGAINST US.

We manufacture products to our customers' specifications which are highly
complex and may at times contain design or manufacturing errors or failures.
Defects have been discovered in products we manufacture in the past and, despite
our quality control and quality assurance efforts, defects may occur in the
future. Defects in the products we manufacture, whether caused by a design,
manufacturing or component failure or error, may result in delayed shipments to
customers or reduced or cancelled customer orders. If these defects occur in
large quantities or too frequently, our business reputation may also be
impaired. In addition, these defects may result in liability claims against us.
The FDA investigates and checks, occasionally on a random basis, compliance with
statutory and regulatory requirements. Violations may lead to penalties or shut
downs of a program or a facility.

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THE PRICE OF OUR COMMON STOCK HAS BEEN AND MAY CONTINUE TO BE VOLATILE AND YOU
MIGHT NOT BE ABLE TO SELL YOUR SHARES AT OR ABOVE THE PUBLIC OFFERING PRICE.

Between October 1, 1999 and August 31, 2000, our stock price has fluctuated
between a low of $12.22 per share and a high of $78.41 per share. On August 31,
2000, the closing price for our common stock was $77.38. The price of our common
stock may fluctuate significantly in response to a number of events and factors
relating to our company, our competitors and the market for our services, many
of which are beyond our control.

In addition, the stock market in general, and especially the Nasdaq
National Market along with market prices for technology companies, in
particular, have experienced extreme volatility that has often been unrelated to
the operating performance of these companies. These broad market and industry
fluctuations may adversely affect the market price of our common stock,
regardless of our operating results.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other
information with the Securities and Exchange Commission. You can read and copy
any materials we file with the Securities and Exchange Commission at its Public
Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549 and at its
regional offices located at Seven World Trade Center, New York, New York 10048
and at 500 West Madison Street, Chicago, Illinois 60661. You can obtain
information about the operations of the Securities and Exchange Commission
Public Reference Room by calling the Securities and Exchange Commission at
1-800-SEC-0330. The Securities and Exchange Commission also maintains a Web site
that contains information we file electronically with the Securities and
Exchange Commission, which you can access over the Internet at
http://www.sec.gov. Our common stock is quoted on the Nasdaq National Market
under the symbol "PLXS," and you can obtain information about us at the offices
of Nasdaq Operations, 1735 K Street, N.W., Washington, D.C. 20006.

This prospectus is part of a registration statement we have filed with the
Securities and Exchange Commission relating to the securities. As permitted by
Securities and Exchange Commission rules, this prospectus does not contain all
of the information we have included in the registration statement and the
accompanying exhibits we filed with the Securities and Exchange Commission. You
may refer to the registration statement and the exhibits for more information
about us and the securities. The registration statement and the exhibits are
available at the Securities and Exchange Commission's Public Reference Room or
through its Web site.

The Securities and Exchange Commission allows us to "incorporate by
reference" the information we file with it, which means that we can disclose
important information to you by referring you to those documents. The
information we incorporate by reference is an important part of this prospectus,
and later information that we file with the Securities and Exchange Commission
will automatically update and supersede some of this information. We incorporate
by reference the documents listed below, and any future filings we make with the
Securities and Exchange Commission under Section 13(a), 13(c), 14 or 15(d) of
the Securities Exchange Act of 1934 until we sell all the securities. The
documents we incorporate by reference are:

- our annual report on Form 10-K for the year ended September 30, 1999

- our reports on Form 10-Q for the quarterly periods ended December 31,
1999, March 31, 2000 and June 30, 2000

- our current reports on Form 8-K dated April 28, 2000, May 23, 2000 (as
amended on August 7, 2000 and August 9, 2000) and July 14, 2000

- the description of our common stock contained in our amended Form 8-A
registration statement (originally filed on July 22, 1986) filed on May
20, 1999, including any amendment or report filed for the purpose of
updating that description

- the description of our preferred stock purchase rights contained in our
Form 8-A registration statement filed on August 17, 1998, including any
amendment or report filed for the purpose of updating that description.

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You may request a copy of these filings, other than an exhibit to the
filings unless we have specifically incorporated that exhibit by reference into
the filing, at no cost, by writing or telephoning us at the following address:

Plexus Corp.
55 Jewelers Park Drive
P.O. Box 156
Neenah, Wisconsin 54957-0156
Attention: Investor Relations
Telephone: (920) 722-3451

You should rely only on the information incorporated by reference or
provided in this prospectus or any prospectus supplement. We have not authorized
anyone else to provide you with different information. We may only use the
prospectus to sell securities if it is accompanied by a prospectus supplement.
We are only offering these securities in states where the offer is permitted.
You should not assume the information in this prospectus or any applicable
prospectus supplement is accurate and complete as of any time after its date.

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USE OF PROCEEDS

Except as otherwise described in the applicable prospectus supplement, we
intend to use the net proceeds from the sale of the securities for one or more
of the following purposes:

- refinance, in part, existing indebtedness

- finance, in part, the cost of acquisitions

- finance capital expenditures and capacity expansion

- general corporate purposes and working capital.

The specific terms of any indebtedness repaid or refinanced with the net
proceeds from the sale of securities will be included in the applicable
prospectus supplement. We may temporarily invest funds not required immediately
for these purposes in short-term marketable securities.

RATIO OF EARNINGS TO FIXED CHARGES

The following table sets forth our ratio of earnings to fixed charges for
the nine months ended June 30, 2000, and the fiscal years ended September 30,
1999, 1998, 1997, 1996 and 1995.

<TABLE>
<CAPTION>
NINE MONTHS FISCAL YEARS ENDED SEPTEMBER 30,
ENDED -------------------------------------
JUNE 30, 2000 1999 1998 1997 1996 1995
------------- ---- ----- ---- ---- ----
<S> <C> <C> <C> <C> <C> <C>
Ratio of Earnings to Fixed Charges(1)............ 14.5x 9.9x 11.7x 7.4x 3.0x 2.6x
</TABLE>

------------
(1) For purposes of computing the ratio of earnings to fixed charges, earnings
consist of income before income taxes, cumulative effect of change in
accounting methods, discontinued operations, extraordinary items and fixed
charges. Fixed charges consist of interest on indebtedness, amortization of
debt expenses and one-third of rent expense which is deemed representative
of an interest factor.

DESCRIPTION OF DEBT SECURITIES

We may issue debt securities in one or more series under an Indenture (the
"Indenture") between us and Bank One Trust Company, N.A., as Trustee, the form
of which is filed as an exhibit to the registration statement. The Indenture
will be subject to, and governed by, the Trust Indenture Act of 1939.

The following summary of certain provisions of the Indenture does not
purport to be complete and is qualified in its entirety by express reference to
the Indenture and the Securities Resolution or the supplemental indenture
authorizing a series. Copies will be filed with the Securities and Exchange
Commission. Capitalized terms used in this section without definition have the
meanings given such terms in the Indenture.

The particular terms of the debt securities offered by a prospectus
supplement will be described in that supplement, along with any applicable
modifications of or additions to the general terms of the debt securities as
described herein and in the Indenture. Accordingly, for a description of the
terms of any series of debt securities, reference must be made to both the
description of the debt securities in this prospectus and the prospectus
supplement.

GENERAL

The Indenture does not limit the amount of debt securities that can be
issued or our ability or that of our subsidiaries to incur, assume or guarantee
debt. In addition, the Indenture does not restrict our ability or that of our
subsidiaries to create or permit liens. It provides that the debt securities may
be issued from time to time in one or more series pursuant to the terms of one
or more Securities Resolutions or supplemental indentures creating the series.

As of the date of this prospectus, there were no debt securities
outstanding under the Indenture. The ranking of a series of debt securities with
respect to all our indebtedness will be established by the Securities Resolution
or supplemental indenture creating the series.

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TERMS

Reference is made to the prospectus supplement for the following terms, if
applicable, of the debt securities offered thereby:

- the designation, aggregate principal amount, currency or composite
currency in which principal or interest may be paid and denominations

- the price at which the debt securities will be issued and, if an index
formula or other method is used, the method for determining amounts of
principal or interest

- the maturity date and other dates, if any, on which principal will be
payable

- the interest rate or rates, if any, or method of calculating the interest
rate or rates

- the date or dates from which interest will accrue and on which interest
will be payable, and the record dates for the payment of interest

- the manner of paying principal and interest

- the place or places where principal and interest will be payable

- the terms of any mandatory or optional redemptions by us including any
sinking fund

- the terms of any conversion or exchange rights

- the terms of any redemptions at the option of holders

- any tax indemnity provisions

- if the debt securities provide that payments of principal or interest may
be made in a currency other than that in which debt securities are
denominated, the manner for determining such payments

- the portion of principal payable upon acceleration of a discounted debt
security (as defined below)

- whether and upon what terms debt securities may be defeased

- whether any events of default or covenants in addition to or in lieu of
those set forth in the Indenture apply

- provisions for electronic issuance of debt securities or for debt
securities in uncertificated form

- the ranking of the debt securities

- any other terms not inconsistent with the provisions of the Indenture,
including any covenants or other terms that may be required or advisable.

We may issue debt securities as registered debt securities, bearer debt
securities or uncertificated debt securities, and in such denominations as
specified in the terms of the series.

In connection with its original issuance, no bearer debt security will be
offered, sold or delivered to any location in the United States, and a bearer
debt security in definitive form may be delivered in connection with its
original issuance only upon presentation of a certificate in a form prescribed
by us to comply with United States laws and regulations.

Registration of transfer of registered debt securities may be requested
upon surrender thereof at any office or agency we maintain for that purpose and
upon fulfillment of all other requirements of the agent.

Securities may be issued under the Indenture as discounted debt securities
to be offered and sold at a substantial discount from the principal amount
thereof. Special U.S. federal income tax and other considerations applicable
thereto will be described in the prospectus supplement relating to any
discounted debt securities. "Discounted debt security" means a security where
the amount of principal due upon acceleration is less than the stated principal
amount payable at maturity.

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COVENANTS

Any covenants that may apply to a particular series of debt securities will
be described in the prospectus supplement relating thereto.

RANKING OF DEBT SECURITIES

Unless stated otherwise in a prospectus supplement, the debt securities
will be unsecured and will rank equally and ratably with our other unsecured and
unsubordinated debt. The debt securities will not be secured by our properties
or assets and will represent unsecured debt. The Indenture does not limit the
ability of any of our subsidiaries to issue, assume or guarantee debt, and the
debt securities will be effectively subordinated to all existing and future
indebtedness and other liabilities and commitments of our subsidiaries.

SUCCESSOR OBLIGOR

The Indenture provides that, unless otherwise specified in the Securities
Resolution establishing a series of debt securities, we shall not consolidate
with or merge into, or transfer all or substantially all of our assets to, any
person in any transaction in which we are not the survivor, unless:

- the person is organized under the laws of the United States or a State
thereof or is organized under the laws of a foreign jurisdiction and
consents to the jurisdiction of the courts of the United States or a
State thereof

- the person assumes by supplemental indenture all of our obligations under
the Indenture, the debt securities and any coupons

- all required approvals of any regulatory body having jurisdiction over
the transaction shall have been obtained

- immediately after the transaction no default (as defined below) exists.

The successor shall be substituted for us, and thereafter all of our
obligations under the Indenture, the debt securities and any coupons shall
terminate.

EXCHANGE OF DEBT SECURITIES

Registered debt securities may be exchanged for an equal aggregate
principal amount of registered debt securities of the same series and date of
maturity in such authorized denominations as may be requested upon surrender of
the registered debt securities at an office or agency we maintain for that
purpose and upon fulfillment of all other requirements of our agent.

DEFAULT AND REMEDIES

Unless the Securities Resolution establishing the series otherwise provides
(in which event the prospectus supplement will so state), an "event of default"
with respect to a series of debt securities will occur if:

- we default in any payment of interest on any debt securities of that
series when the same becomes due and payable and the default continues
for a period of 30 days

- we default in the payment of the principal and premium, if any, of any
debt securities of the series when the same becomes due and payable at
maturity or upon redemption, acceleration or otherwise

- we default in the payment or satisfaction of any sinking fund obligation
with respect to any debt securities of that series as required by the
Securities Resolution establishing that series

- we default in the performance of any of our other agreements applicable
to the series and the default continues for 60 days after the notice
specified below

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- pursuant to or within the meaning of any Bankruptcy Law (as defined
below), we:

(A) commence a voluntary case

(B) consent to the entry of an order for relief against us in an
involuntary case

(D) make a general assignment for the benefit of our creditors

- a court of competent jurisdiction enters an order or decree under any
Bankruptcy Law that:

(A) is for relief against us in an involuntary case

(B) appoints a Custodian for us or for all or substantially all of our
property

- there occurs any other event of default provided for in such series.

The term "Bankruptcy Law" means Title 11, U.S. Code or any similar federal
or state law for the relief of debtors. The term "Custodian" means any receiver,
trustee, assignee, liquidator or a similar official under any Bankruptcy Law.

"Default" means any event which is, or after notice or passage of time
would be, an event of default. A default is not an event of default until the
Trustee or the holders of at least 25% in principal amount of the series notify
us of the default and we do not cure the default within the time specified after
receipt of the notice. If an event of default occurs and is continuing on a
series, the Trustee by notice to us, or the holders of at least 25% in principal
amount of the series, may declare the principal of and accrued interest on all
the debt securities of the series to be due and payable immediately. Discounted
debt securities may provide that the amount of principal due upon acceleration
is less than the stated principal amount. The holders of a majority in principal
amount of the series, by notice to the Trustee, may rescind an acceleration and
its consequences if the rescission would not conflict with any judgment or
decree and if all existing events of default on the series have been cured or
waived except nonpayment of principal or interest that has become due solely
because of the acceleration. If an event of default occurs and is continuing on
a series, the Trustee may pursue any available remedy to collect principal or
interest then due on the series, to enforce the performance of any provision
applicable to the series, or otherwise to protect the rights of the Trustee and
holders of the series.

The Trustee may require indemnity satisfactory to it before it enforces the
Indenture or the debt securities of the series. Subject to certain limitations,
holders of a majority in principal amount of the debt securities of the series
may direct the Trustee in its exercise of any trust or power with respect to
such series. Except in the case of default in payment on a series, the Trustee
may withhold from holders of that series notice of any continuing default if it
determines that withholding the notice is in the interest of holders of the
series. We are required to furnish the Trustee annually a brief certificate as
to our compliance with all conditions and covenants under the Indenture.

The Indenture does not have a cross-default provision. Thus, a default by
us on any other debt, including any other series of debt securities, would not
constitute an event of default. A Securities Resolution may provide for a
cross-default provision, in which case the prospectus supplement will describe
the terms of that provision.

AMENDMENTS AND WAIVERS

The Indenture and the debt securities or any coupons of the series may be
amended, and any default may be waived as follows: Unless the Securities
Resolution otherwise provides (in which event the prospectus supplement will so
state), we and the Trustee may amend the debt securities, the Indenture and any
coupons with the written consent of the holders of a majority in principal
amount of the debt securities of all series affected voting as one class. Unless
the Securities Resolution otherwise provides (in
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<PAGE> 63

which event the prospectus supplement will so state), a default on a particular
series may be waived with the consent of the holders of a majority in principal
amount of the debt securities of the series. However, without the consent of
each debt security holder affected, no amendment or waiver may:

- reduce the amount of debt securities whose holders must consent to an
amendment or waiver

- reduce the interest on or change the time for payment of interest on any
debt security

- change the fixed maturity of any debt security or change the amount or
time for any payment of any sinking fund or similar fund

- reduce the principal of any non-discounted debt security

- reduce the amount of the principal of any discounted debt security that
would be due on acceleration, upon redemption or upon maturity

- change the currency in which the principal of or interest on a debt
security is payable

- make any change that materially adversely affects the right to convert or
exchange any debt security

- waive any default in payment of interest on or principal of a debt
security.

Without the consent of any debt security holder, we and the Trustee may
amend the Indenture, the debt securities or any coupons to:

- cure any ambiguity, omission, defect, or inconsistency

- provide for assumption of our obligations to debt security holders in the
event of a merger or consolidation requiring such assumption

- provide that specific provisions of the Indenture shall not apply to a
series of debt securities not previously issued

- create a series and establish its terms

- provide for a separate Trustee for one or more series

- make any change that does not materially adversely affect the rights of
any debt security holder.

LEGAL DEFEASANCE AND COVENANT DEFEASANCE

Debt securities of a series may be defeased in accordance with their terms
and, unless the Securities Resolution establishing the terms of the series
otherwise provides, as set forth in the Indenture and described briefly below.
We, at any time, may terminate as to a series all of our obligations (except
certain obligations, including obligations with respect to the defeasance trust
and obligations to register the transfer or exchange of a Security, to replace
destroyed, lost or stolen debt securities and coupons, and to maintain paying
agencies in respect of the debt securities) with respect to the debt securities
of the series and any related coupons and the Indenture ("legal defeasance").
We, at any time, may terminate as to a series our obligations, if any, with
respect to the debt securities and coupons of the series under any restrictive
covenants which may be applicable to a particular series ("covenant
defeasance").

We may exercise our legal defeasance option notwithstanding our prior
exercise of our covenant defeasance option. If we exercise our legal defeasance
option, a series may not be accelerated because of an event of default. If we
exercise our covenant defeasance option, a series may not be accelerated by
reference to any restrictive covenants which may be applicable to the particular
series deferred.

To exercise either defeasance option as to a series, we must:

- irrevocably deposit in trust with the Trustee or another trustee money or
U.S. government obligations

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<PAGE> 64

- deliver a certificate from a nationally recognized firm of independent
accountants expressing their opinion that the payments of principal and
interest when due on the deposited U.S. government obligations, without
reinvestment, plus any deposited money without investment will provide
cash at such times and in such amounts as will be sufficient to pay the
principal and interest when due on all debt securities of the series to
maturity or redemption, as the case may be

- comply with other specified conditions; in particular, we must obtain an
opinion of tax counsel that the defeasance will not result in recognition
of any gain or loss to holders for federal income tax purposes.

"U.S. government obligations" means direct obligations of the United States
or an agency or instrumentality of the United States, the payment of which is
unconditionally guaranteed by the United States, which, in either case, have the
full faith and credit of the United States of America pledged for payment and
which are not callable at the issuer's option, or certificates representing an
ownership interest in such obligations.

REGARDING THE TRUSTEE

Bank One Trust Company, N.A. will act as Trustee and registrar for debt
securities issued under the Indenture and, unless otherwise indicated in a
prospectus supplement, the Trustee will also act as transfer agent and paying
agent with respect to the debt securities. We may remove the Trustee with or
without cause if we so notify the Trustee three months in advance and if we are
not in default during the three-month period. The Trustee, in its individual or
any other capacity, may make loans to, accept deposits from, and perform
services for us or our affiliates, and may otherwise deal with us or our
affiliates, as if it were not Trustee.

DESCRIPTION OF CAPITAL STOCK

Our authorized capital stock consists of 60,000,000 shares of common stock,
$0.01 par value per share, and 5,000,000 shares of preferred stock, $.01 par
value per share. Our articles of incorporation currently designate 1,000,000 of
the preferred shares as Series A Junior Participating Preferred Stock of which
none is issued or outstanding.

COMMON STOCK

As of September 1, 2000, there were approximately 37,021,524 shares of
common stock outstanding held of record by approximately 900 shareholders. As of
August 31, 2000, there were outstanding options to purchase approximately
4,090,000 shares of common stock, of which approximately 2,299,000 were
immediately exercisable. Our common stock is quoted on the Nasdaq National
Market under the symbol "PLXS."

Holders of common stock are entitled to one vote for each share held on all
matters to be voted upon by the shareholders and do not have cumulative rights.
Accordingly, holders of a majority of the shares of common stock entitled to
vote in any election of directors may elect all of the directors standing for
election. Holders of common stock are entitled to receive ratably such
dividends, if any, as may be declared by the board of directors out of funds
legally available therefor, subject to any preferential dividend payable to the
outstanding preferred stock. Upon our liquidation, dissolution or winding up,
the holders of common stock are entitled to receive ratably our net assets
available after the payment of all debts and other liabilities and subject to
the prior rights of any outstanding preferred stock.

Holders of the common stock have no preemptive, subscription, redemption or
conversion rights. The outstanding shares of common stock are validly issued,
fully paid and nonassessable. However, Wisconsin law imposes personal liability
on shareholders of Wisconsin corporations for debts owed to employees for
services performed, but not exceeding six months service in any one case. While
the relevant statute limits this liability to the par value of the shares held,
this limitation has been interpreted by a Wisconsin trial court to mean the
consideration paid to the corporation for such shares. This decision was
affirmed by a
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<PAGE> 65

split decision of the Wisconsin Supreme Court without a written opinion,
although the decision was subsequently overturned on other grounds.

The rights, preferences and privileges of holders of common stock are
subject to, and may be adversely affected by, the rights of the holders of
shares of any series of preferred stock which we may determine and issue in the
future, as described below. Currently, there are no shares of preferred stock
outstanding.

PREFERRED STOCK

Our board is authorized without further shareholder approval to issue from
time to time up to an aggregate of 5,000,000 shares of preferred stock in one or
more series and to fix or alter the designations, preferences, rights and any
qualifications, limitations or restrictions of the shares of each such series
thereof. These include the dividend rights, dividend rates, conversion rights,
voting rights, terms of redemption (including sinking fund provisions),
redemption of price or prices, liquidation preferences and the number of shares
constituting any series or designations of such series. The issuance of
preferred stock may have the effect of delaying, deferring or preventing a
change of control of Plexus. We have no present plans to issue any shares of
preferred stock, but have designated 1,000,000 shares of Series A Junior
Participating Preferred Stock in connection with the adoption of our shareholder
rights plan, described below.

SHAREHOLDER RIGHTS PLAN

On August 13, 1998, our board of directors adopted a shareholder rights
plan which provides for one preferred stock purchase right for each outstanding
common stock. The rights agreement provides that until the rights distribution
date, the rights will be transferred with and only with the common stock until
the triggering event. The rights are evidenced by common stock certificates. The
rights are non-exercisable until the rights distribution date. The rights will
expire on August 11, 2008.

Each right entitles shareholders to buy one-one hundredth of a share of
newly created Series A Junior Participating Preferred Stock at an exercise price
of $54.00, subject to adjustment, in the event a person acquires or makes a
tender exchange offer for 15% or more of the outstanding stock. In such event,
each right entitles the holder, other than the person acquiring 15% or more of
the outstanding stock, to purchase shares of common stock with market value of
twice the rights' exercise price. In addition, if we are acquired in a merger or
other business combination or if we sell more than 50% of our consolidated
assets or voting power, our shareholders are entitled (other than the acquiror)
to purchase for the purchase price shares of the common stock of the acquiring
entity or its parents having a market value of two times the exercise price. At
any time prior to such event, the board of directors may redeem the rights at
one cent per share per right. The existence of the rights may, under certain
circumstances, render more difficult or discourage attempts to acquire us.

STATUTORY PROVISIONS APPLICABLE TO COMMON STOCK

Business Combination Statute. Sections 180.1140 to 180.1144 of the
Wisconsin Business Corporation Law regulate a broad range of business
combinations between a resident domestic corporation and an interested
shareholder. A business combination is defined to include any of the following
transactions:

- merger or share exchange

- sale, lease, exchange, mortgage, pledge, transfer or other disposition of
assets equal to 5% or more of the market value of the stock or assets of
the company or 10% of its earning power or income

- issuance of stock or rights to purchase stock with a market value equal
to 5% or more of the outstanding stock

- adoption of a plan of liquidation or dissolution.

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<PAGE> 66

A "resident domestic corporation" is defined to mean a Wisconsin
corporation that has a class of voting stock that is registered or traded on a
national securities exchange or that is registered under Section 12(g) of the
Exchange Act and that, as of the relevant date, satisfies any of the following:

- its principal offices are located in Wisconsin

- it has significant business operations located in Wisconsin

- more than 10% of the holders of record of its shares are residents of
Wisconsin

- more than 10% of its shares are held of record by residents of Wisconsin.

Plexus is a resident domestic corporation for purposes of these statutory
provisions.

An interested shareholder is defined to mean a person who beneficially
owns, directly or indirectly, 10% of the voting power of the outstanding voting
stock of a corporation or who is an affiliate or associate of the corporation
and beneficially owned 10% of the voting power of the then outstanding voting
stock within the last three years.

Under this law, we cannot engage in a business combination with an
interested shareholder for a period of three years following the date such
person becomes an interested shareholder, unless the board of directors approved
the business combination or the acquisition of the stock that resulted in the
person becoming an interested shareholder before such acquisition. We may engage
in a business combination with an interested shareholder after the three-year
period with respect to that shareholder expires only if one or more of the
following conditions is satisfied:

- the board of directors approved the acquisition of the stock prior to
such shareholder's acquisition date

- the business combination is approved by a majority of the outstanding
voting stock not beneficially owned by the interested shareholder

- the consideration to be received by shareholders meets certain fair price
requirements of the statute with respect to form and amount.

Fair Price Statute. The Wisconsin Business Corporation Law also provides,
in Sections 180.1130 to 180.1133, that certain mergers, share exchanges or
sales, leases, exchanges or other dispositions of assets in a transaction
involving a significant shareholder and a resident domestic corporation such as
Plexus require a supermajority vote of shareholders in addition to any approval
otherwise required, unless shareholders receive a fair price for their shares
that satisfies a statutory formula. A significant shareholder for this purpose
is defined as a person or group who beneficially owns, directly or indirectly,
10% or more of the voting stock of the corporation, or is an affiliate of the
corporation and beneficially owned, directly or indirectly, 10% or more of the
voting stock of the corporation within the last two years. Any such business
combination must be approved by 80% of the voting power of the corporation's
stock and at least two-thirds of the voting power of the corporation's stock not
beneficially held by the significant shareholder who is party to the relevant
transaction or any of its affiliates or associates, in each case voting together
as a single group, unless the following fair price standards have been met:

- the aggregate value of the per share consideration is equal to the
highest of:

(A) the highest price paid for any common shares of the corporation by
the significant shareholder in the transaction in which it became
a significant shareholder or within two years before the date of
the business combination

(B) the market value of the corporation's shares on the date of
commencement of any tender offer by the significant shareholder,
the date on which the person became a significant shareholder or
the date of the first public announcement of the proposed business
combination, whichever is higher

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- either cash, or the form of consideration used by the significant
shareholder to acquire the largest number of shares, is offered.

Control Share Voting Restrictions. Under Section 180.1150 of the Wisconsin
Business Corporation Law, unless otherwise provided in the articles of
incorporation, the voting power of shares of a resident domestic corporation
held by any person or group of persons acting together in excess of 20% of the
voting power in the election of directors is limited (in voting on any matter)
to 10% of the full voting power of those shares. This restriction does not apply
to shares acquired directly from the resident domestic corporation, in certain
specified transactions, or in a transaction in which the corporation's
shareholders have approved restoration of the full voting power of the otherwise
restricted shares. Because of the 10% threshold contained in Wisconsin's
business combination statute discussed above, this control share threshold of
20% may not be implicated unless the board of directors first approves a
transaction that permits a shareholder to exceed the 10% ownership level.

Defensive Action Restrictions. Section 180.1134 of the Wisconsin Business
Corporation Law provides that, in addition to the vote otherwise required by law
or the articles of incorporation of a resident domestic corporation, the
approval of the holders of a majority of the shares entitled to vote is required
before such corporation can take certain action while a takeover offer is being
made or after a takeover offer has been publicly announced and before it is
concluded. This statute requires shareholder approval for the corporation to do
either of the following:

- acquire more than 5% of its outstanding voting shares at a price above
the market price from any individual or organization that owns more than
3% of the outstanding voting shares and has held such shares for less
than two years, unless a similar offer is made to acquire all voting
shares and all securities which may be converted into voting shares

- sell or option assets of the corporation which amount to 10% or more of
the market value of the corporation, unless the corporation has at least
three independent directors (directors who are not officers or employees)
and a majority of the independent directors vote not to have this
provision apply to the corporation.

The foregoing provisions of Wisconsin law and the Plexus shareholder rights
agreement, the ability to issue additional shares of the common stock and
preferred stock without further shareholder approval (except as may be required
by the Nasdaq National Market corporate governance standards) and the ability of
the board of directors to fix the designations of further classes of preferred
stock (including the ability to issue preferred stock with substantial voting
rights) could have the effect, among others, of discouraging take-over proposals
for or impeding a business combination involving Plexus.

BOOK-ENTRY

The Depository Trust Company ("DTC") may act as securities depository for
the securities, in which case the applicable prospectus supplement will so
provide. The securities will be issued only as fully registered securities
registered in the name of Cede & Co. (DTC's partnership nominee). One or more
fully registered global certificates will be issued for the securities
representing the aggregate principal amount of the debt securities or the number
of shares of common stock offered by the applicable prospectus supplement and
will be deposited with DTC.

DTC is a limited-purpose trust company organized under the New York Banking
Law, a "banking organization" within the meaning of the New York Banking Law, a
member of the Federal Reserve System, a "clearing corporation" within the
meaning of the New York Uniform Commercial Code, and a "clearing agency"
registered pursuant to the provisions of Section 17A of the 1934 Act, as
amended. DTC holds securities that its participants (the "Direct Participants")
deposit with DTC. DTC also facilitates the settlement among Direct Participants
of securities transactions, such as transfers and pledges, in deposited

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securities through electronic computerized book-entry changes in Direct
Participants' accounts, thereby eliminating the need for physical movement of
securities certificates. Direct Participants include securities brokers and
dealers, banks, trust companies, clearing corporations, and certain other
organizations. DTC is owned by a number of its Direct Participants and by the
New York Stock Exchange, Inc., the American Stock Exchange, Inc. and the
National Association of Securities Dealers, Inc. Access to the DTC system is
also available to others such as securities brokers and dealers, banks, and
trust companies that clear through or maintain a custodial relationship with a
Direct Participant, either directly or indirectly (the "Indirect Participants,"
and together with the Direct Participants, the "Participants"). The rules
applicable to DTC and its Participants are on file with the Commission.

Purchases of the securities within the DTC system must be made by or
through Direct Participants which will receive a credit for the securities on
DTC's records. The ownership interest of each actual purchaser of each security
(a "beneficial owner") will in turn be recorded on the Direct and Indirect
Participants' respective records. Beneficial owners will not receive written
confirmation from DTC of their purchase, but beneficial owners are expected to
receive written confirmations providing details of the transaction, as well as
periodic statements of their holdings, from the Direct or Indirect Participant
through which the beneficial owner entered into the transaction. Transfers of
ownership interest in the securities will be effected by entries made on the
books of Participants acting on behalf of beneficial owners. Beneficial owners
will not receive certificates representing their ownership interest in
securities except in the event that use of the book-entry system for the
securities is discontinued.

The deposit of the securities with DTC and their registration in the name
of Cede & Co. effect no change in beneficial ownership. DTC has no knowledge of
the actual beneficial owners of the securities; DTC's records reflect only the
identity of the Direct Participants to whose accounts such securities are
credited, which may or may not be the beneficial owners. The Participants will
remain responsible for keeping account of their holdings on behalf of their
customers.

Conveyance of notices and other direct communications by DTC to Direct
Participants, by Direct Participants to Indirect Participants, and by Direct
Participants and Indirect Participants to beneficial owners will be governed by
arrangements among them, subject to any statutory or regulatory requirements as
may be in effect from time to time.

Redemption notices shall be sent to Cede & Co. If less than all of the
securities of an issue are being redeemed, DTC's practice will determine by lot
the amount of the interest of each Direct Participant in such series to be
redeemed.

Neither DTC nor Cede & Co. will consent or vote with respect to the
securities. Under its usual procedures, DTC mails an omnibus proxy (an "omnibus
proxy") to the Participants as soon as possible after the record date. The
omnibus proxy assigns Cede & Co.'s consenting or voting rights to those Direct
Participants to whose accounts the securities are credited on the record date
(identified in a listing attached to the omnibus proxy).

Principal, premium, if any, and interest on the debt securities and
dividends on common stock, if applicable, will be paid to DTC. DTC's practice is
to credit Direct Participants' accounts on the relevant payment date in
accordance with their respective holdings shown on DTC's records unless DTC has
reason to believe that it will not receive payment on such payment date.
Payments by Participants to beneficial owners will be governed by standing
instructions and customary practices, as is the case with securities held for
the accounts of customers in bearer form or registered in "street-name," and
will be the responsibility of such Participant and not of DTC, the underwriters,
or Plexus, subject to any statutory or regulatory requirements as may be in
effect from time to time. Payment of principal, premium, if any, and interest on
the debt securities and dividends on common stock, if applicable, to DTC is the
responsibility of the Company or the Trustee. Disbursement of such payments to
Direct Participants is the responsibility of DTC, and disbursement of such
payments to the beneficial owners is the responsibility of Direct and Indirect
Participants.

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DTC may discontinue providing its services as securities depository with
respect to the securities at any time by giving us reasonable notice. Under such
circumstances and in the event that a successor securities depository is not
obtained, certificates for the securities are required to be printed and
delivered. In addition, we may decide to discontinue use of the system of
book-entry transfers through DTC (or any successor securities depository). In
that event, certificates for the securities will be printed and delivered.

We will not have any responsibility or obligation to Participants or to the
persons for whom they act as nominees with respect to the accuracy of the
records of DTC, its nominees or any Direct or Indirect Participant with respect
to any ownership interest in the securities, or with respect to payments or
providing of notice to the Direct Participants, the Indirect Participants or the
beneficial owners.

So long as Cede & Co. is the registered owner of the securities, as nominee
of DTC, references herein to holders of the securities shall mean Cede & Co. or
DTC and shall not mean the beneficial owners of the securities.

The information in this section concerning DTC and DTC's book-entry system
has been obtained from DTC. None of Plexus, the Trustees or the underwriters
take any responsibility for the accuracy or completeness thereof.

PLAN OF DISTRIBUTION

We may sell the securities offered under this prospectus through
underwriters, agents or dealers or directly to purchasers.

UNDERWRITERS

The relevant prospectus supplement will identify any agents or underwriters
and describe their compensation, including any underwriting discount, placement
fee or other commission. The prospectus supplement will also describe other
terms of the offering, including any discounts or concessions allowed or
reallowed or paid to dealers and any securities exchange or automated quotation
systems on which any offered debt securities may be listed or quoted.

The distribution of securities under this prospectus may occur from time to
time in one or more transactions at a fixed price or prices, which may be
changed, at market prices prevailing at the time of sale, at prices related to
those prevailing market prices or at negotiated prices.

AGENTS AND DIRECT SALES

If the applicable prospectus supplement indicates, we will authorize
dealers or our agents to solicit offers by various institutions to purchase
offered securities from us pursuant to contracts that provide for payment and
delivery on a future date. We must approve all institutions, but they may
include, among others:

- commercial and savings banks

- insurance companies

- pension funds

- investment companies

- educational and charitable institutions.

The institutional purchaser's obligations will be subject only to the
condition that the purchase of the securities is permitted at the time of
delivery. The dealers and our agents will not be responsible for the validity or
performance of the contract.

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GENERAL INFORMATION

Underwriters, dealers and agents participating in a sale of securities may
be deemed to be underwriters as defined in the Securities Act, and any discounts
and commissions received by them and any profit realized by them on resale of
the securities may be deemed to be underwriting discounts and commissions under
the Securities Act. We may have agreements with the agents, underwriters and
dealers to indemnify them against various civil liabilities, including
liabilities under the Securities Act, or to contribute to payments that the
agents, underwriters or dealers may be required to make as a result of those
civil liabilities.

Our common stock is quoted on the Nasdaq National Market under the symbol
"PLXS." Unless we indicate differently in a prospectus supplement, we will not
list the debt securities on any securities exchange or seek to have them
included on the Nasdaq National Market or any other automated quotation system.
If we sell a security offered under this prospectus to an underwriter for public
offering and sale, the underwriter may make a market for that security, but is
not obligated to do so. Therefore, we cannot give any assurances to you
concerning the liquidity of any security offered under this prospectus.

Agents and underwriters and their affiliates may be customers of, engage in
transactions with or perform services for us or our subsidiary companies in the
ordinary course of business.

CERTAIN LEGAL MATTERS

The validity of the securities to be sold pursuant to this prospectus will
be passed upon for us by Quarles & Brady LLP, Milwaukee, Wisconsin, counsel to
the Company. Any underwriters or agents will be advised about other issues
relating to a particular offering by Jones, Day, Reavis & Pogue, Chicago,
Illinois.

EXPERTS

Our consolidated financial statements and the related financial statement
schedules incorporated in this prospectus by reference from our Annual Report on
Form 10-K for the fiscal year ended September 30, 1999 have been audited by
PricewaterhouseCoopers LLP, independent accountants, as stated in their reports,
which are incorporated herein by reference, and have been so incorporated in
reliance upon the reports of such firm given upon their authority as experts in
accounting and auditing.

The financial statements of SeaMED Corporation, a company acquired by
Plexus in 1999, for its fiscal years ended June 30, 1998 and 1997 (not presented
separately herein), which are referred to in the report of
PricewaterhouseCoopers on the Plexus financial statements, have been audited by
Ernst & Young LLP, independent auditors, as set forth in their report included
in our annual report on Form 10-K for the fiscal year ended September 30, 1999
and incorporated herein by reference. The reference to the SeaMED financial
statements was made in reliance upon such report given on authority of such firm
as experts in accounting and auditing.

The financial statements of Contract Electronics Manufacturing Services
Operations of Elamex, S.A. de C.V. as of and for the year ended December 31,
1999, incorporated in this prospectus by reference from the Current Report on
Form 8-K/A of Plexus dated May 23, 2000, have been audited by Deloitte & Touche
LLP, independent auditors, as stated in their report, which is incorporated
herein by reference, and has been so incorporated in reliance upon the report of
such firm given upon their authority as experts in accounting and auditing.

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[PLEXUS LOGO]
<PAGE> 72

SUBJECT TO COMPLETION, DATED SEPTEMBER 21, 2000

[PLEXUS LOGO]

3,000,000 SHARES

COMMON STOCK

---------------------------

INVESTING IN OUR COMMON STOCK INVOLVES RISKS.
SEE "RISK FACTORS" BEGINNING ON PAGE 2 OF THE ACCOMPANYING PROSPECTUS.

---------------------------

THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION HAS NOT APPROVED
OR DISAPPROVED THESE SECURITIES, OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL
AND COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

Plexus Corp. has granted the underwriters a 30-day option to purchase
up to an additional 450,000 shares of common stock to cover over-allotments.

---------------------------

ROBERTSON STEPHENS INTERNATIONAL

SG COWEN
THOMAS WEISEL PARTNERS LLC
ROBERT W. BAIRD & CO.

THE DATE OF THIS PROSPECTUS SUPPLEMENT IS , 2000.