<PAGE>
Long Term Portfolio Series 120
File No. 33-28194
Investment Company Act No. 811-3676
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
POST-EFFECTIVE AMENDMENT NO. 5
TO FORM S-6
For Registration Under the Securities Act of 1933 of Securities
of Unit Investment Trust Registered on Form N-8B-2
A. Exact name of Trust:
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
B. Name of Depositor:
DEAN WITTER REYNOLDS INC.
C. Complete address of Depositor's principal executive
office:
DEAN WITTER REYNOLDS INC.
Two World Trade Center
New York, New York 10048
D. Name and complete address of agent for service:
Mr. Michael D. Browne
Dean Witter Reynolds Inc.
Unit Trust Department
Two World Trade Center, 59th Floor
New York, New York 10048
Copy to:
Kenneth W. Orce, Esq.
Cahill Gordon & Reindel
80 Pine Street
New York, New York 10005
/x/ Check box if it is proposed that this filing should
become effective immediately upon filing pursuant to
paragraph(b) of Rule 485.
<PAGE>
Cross Reference Sheet
Pursuant to Rule 404(c) of Regulation C
under the Securities Act of 1933
(Form N-8B-2 Items required by Instruction 1
as to Prospectus on Form S-6)
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
I. Organization and General Information
1. (a) Name of Trust Front Cover
(b) Title of securities issued
2. Name and address of Depositor Table of Contents
3. Name and address of Trustee Table of Contents
4. Name and address of principal Table of Contents
Underwriter
5. Organization of Trust Introduction
6. Execution and termination of Introduction; Amendment
Indenture and Termination of the
Indenture
7. Changes of name *30
8. Fiscal Year Included in Form N-8B-2
9. Litigation *30
II. General Description of the Trust
and Securities of the Trust
10. General Information regarding
Trust's Securities and Rights
of Holders
(a) Type of Securities Rights of Unit Holders
(Registered or Bearer)
(b) Type of Securities Administration of the
(Cumulative or Distribu- Trust-Distribution
tive)
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
(c) Rights of Holders as to Redemption; Public Of-
Withdrawal or Redemption fering of Units-
Secondary Market
(d) Rights of Holders as to Public Offering of
conversion, transfer, etc. Units-Secondary Market;
Exchange Option; Re-
demption; Rights of
Unit Holders-
Certificates
(e) Lapses or defaults with *30
respect to periodic pay-
ment plan certificates
(f) Voting rights as to Secu- Rights of Unit Holders-
rities under the Indenture Certain Limitations
(g) Notice to Holders as to Amendment and Termina-
change in: tion of the Indenture
1) Assets of Trust Administration of the
Trust-Reports to Unit
Holders; The Trust-
Summary Description of
the Portfolios
2) Terms and Conditions Amendment and Termina-
of Trust's Securities tion of the Indenture
3) Provisions of Trust Amendment and Termina-
tion of the Indenture
4) Identity of Depositor Sponsor; Trustee
and Trustee
(h) Security Holders' consent
required to change:
1) Composition of assets Amendment and Termina-
of Trust tion of the Indenture
2) Terms and conditions Amendment and Termina-
of Trust's Securities tion of the Indenture
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
3) Provisions of Inden- Amendment and Termina-
ture tion of the Indenture
4) Identity of Depositor *30
and Trustee
(i) Other Provisions Cover of Prospectus;
Tax Status
11. Type of securities comprising The Trust-Summary De-
units scription of the Port-
folios; Objectives and
Securities Selection;
The Trust-Special Con-
siderations
12. Type of securities comprising *30
periodic payment certificates
13. (a) Load, fees, expenses, etc. Summary of Essential
Information; Public Of-
fering of Units-Public
Offering Price;-Profit
of Sponsor;-Volume Dis-
count; Expenses and
Charges
(b) Certain information re- *30
garding periodic payment
certificates
(c) Certain percentages Summary of Essential
Information; Public Of-
fering of Units-Public
Offering Price;-Profit
of Sponsor;-Volume Dis-
count
(d) Price differentials Public Offering of
Units - Public Offering
Price
(e) Certain other fees, etc. Rights of Unit Holders
payable by holders - Certificates
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
(f) Certain profits receivable Redemption -- Purchase
by depositor, principal by the Sponsors of
underwriters, trustee or Units Tendered for Re-
affiliated persons demption
(g) Ratio of annual charges to *30
income
14. Issuance of trust's securities Introduction; Rights of
Unit Holders - Certifi-
cates
15. Receipt and handling of pay- Public Offering of
ments from purchasers Units-Profit of Sponsor
16. Acquisition and disposition of Introduction; Amendment
underlying securities and Termination of the
Indenture; Objectives
and Securities Selec-
tion; The Trust-Summary
Description of the
Portfolio; Sponsor-
Responsibility
17. Withdrawal or redemption by Se- Redemption; Public Of-
curity Holders fering of
Units-Secondary Market
18. (a) Receipt and disposition of Administration of the
income Trust; Reinvestment
Programs
(b) Reinvestment of distribu- Reinvestment Programs
tions
(c) Reserves or special fund Administration of the
Trust-Distribution
(d) Schedule of distribution *30
19. Records, accounts and report Administration of the
Trust-Records and Ac-
counts;-Reports to Unit
Holders
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
20. Certain miscellaneous provi- Amendment and Termina-
sions of the Indenture tion of the Indenture;
Sponsor - Limitation on
Liability - Resigna-
tion; Trustee -- Limi-
tation on Liability-
Resignation
21. Loans to security holders *30
22. Limitations on liability Sponsor, Trustee;
Evaluator - Limitation
on Liability
23. Bonding arrangements Included on Form N-8B-2
24. Other material provisions of *30
the Indenture
III. Organization Personnel and
Affiliated Persons of Depositor
25. Organization of Depositor Sponsor
26. Fees received by Depositor Expenses and Charges -
Fees; Public Offering
of Units-Profit of
Sponsor
27. Business of Depositor Sponsor and Included in
Form N-8B-2
28. Certain information as to offi- Included in Form N-8B-2
cials and affiliated persons of
Depositor
29. Voting securities of Depositor Included in Form N-8B-2
30. Persons controlling Depositor *30
31. Payments by Depositor for cer- *30
tain other services
32. Payments by Depositor for cer- *30
tain other services rendered to
trust
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
33. Remuneration of employees of *30
Depositor for certain services
rendered to trust
34. Remuneration of other persons
for certain services rendered
*30
to trust
IV. Distribution and Redemption of Securities
35. Distribution of trust's securi- Public Offering of
ties by states Units-Public Distribu-
tion
36. Suspension of sales of trust's *30
securities
37. Revocation of authority to dis- *30
tribute
38. (a) Method of distribution Public Offering of
(b) Underwriting agreements Units
(c) Selling agreements
39. (a) Organization of principal Sponsor
underwriter
(b) N.A.S.D. membership of
principal underwriter
40. Certain fees received by prin- Public Offering of
cipal underwriter Units-Profit of Sponsor
41. (a) Business of principal un- Sponsor
derwriter
(b) Branch officers of princi- *30
pal underwriter
(c) Salesman of principal un- *30
derwriter
42. Ownership of trust's securities *30
by certain persons
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
43. Certain brokerage commissions *30
received by principal under-
writer
44. (a) Method of valuation Public Offering of
Units
(b) Schedule as to offering *30
price
(c) Variation in offering Public Offering of
price to certain persons Units--Volume Discount;
Exchange Option
45. Suspension of redemption rights *30
46. (a) Redemption valuation Public Offering of
Units-Secondary Market;
Redemption
(b) Schedule as to redemption *30
price
47. Maintenance of position in un- See items 10(d), 44 and
derlying securities 46
V. Information concerning the Trustee or Custodian
48. Organization and regulation of Trustee
Trustee
49. Fees and expenses of Trustee Expenses and Charges
50. Trustee's lien Expenses and Charges
VI. Information concerning Insurance
of Holders of Securities
51. (a) Name and address of Insur- *30
ance Company
(b) Type of policies *30
(c) Type of risks insured and *30
excluded
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
(d) Coverage of policies *30
(e) Beneficiaries of policies *30
(f) Terms and manner of can- *30
cellation
(g) Method of determining pre- *30
miums
(h) Amount of aggregate premi- *30
ums paid
(i) Who receives any part of *30
premiums
(j) Other material provisions *30
of the Trust relating to
insurance
VII. Policy of Registrant
52. (a) Method of selecting and Introduction; Objec-
eliminating securities tives and Securities
from the Trust Selection; The Trust -
Summary Description of
the Portfolio; Sponsor
- Responsibility
(b) Elimination of securities *30
from the Trust
(c) Policy of Trust regarding Introduction; Objec-
substitution and elimina- tives and Securities
tion of securities Selection; Sponsor -
Responsibility
(d) Description of any funda- *30
mental policy of the Trust
53. Taxable status of the Trust Cover of Prospectus;
Tax Status
VIII. Financial and Statistical Information
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
Form N-8B-2 Form S-6
Item Number Heading in Prospectus
54. Information regarding the *30
Trust's past ten fiscal years
55. Certain information regarding *30
periodic payment plan certifi-
cates
56. Certain information regarding *30
periodic payment plan certifi-
cates
57. Certain information regarding *30
periodic payment plan certifi-
cates
58. Certain information regarding *30
periodic payment plan certifi-
cates
59. Financial statements Statement of Financial
(Instruction 1(c) to Form S-6) Condition
__________________
*30 Not applicable, answer negative or not required.
<PAGE>
LOGO
DEAN WITTER SELECT
MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
(Unit Investment Trusts)
_______________________________________________________________
This Trust was formed for the purpose of providing interest in-
come which in the opinion of bond counsel is, under existing
law, excludable from gross income for Federal income tax pur-
poses (except in certain instances depending on the Unit Hold-
ers) through investment in a fixed portfolio consisting primar-
ily of investment grade long-term state, municipal and public
authority debt obligations. The value of the Units of the
Trust will fluctuate with the value of the portfolio of under-
lying Securities. Minimum Purchase: 1 Unit.
_______________________________________________________________
This Prospectus consists of two parts. Part A contains a Sum-
mary of Essential Information and descriptive material relating
to the Trust, and the portfolio and financial statements of the
Trust. Part B contains a general description of the Trust.
Part A may not be distributed unless accompanied by Part B.
_______________________________________________________________
The Initial Public Offering of Units in the Trust has been com-
pleted. The Units offered hereby are issued and outstanding
Units which have been acquired by the Sponsor either by pur-
chase from the Trustee of Units tendered for redemption or in
the Secondary Market.
<PAGE>
_______________________________________________________________
Sponsor: LOGO DEAN WITTER REYNOLDS INC.
_______________________________________________________________
THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE
SECURITIES AND EXCHANGE COMMISSION OR ANY STATE SECURITIES
COMMISSION NOR HAS THE SECURITIES AND EXCHANGE COMMISSION OR
ANY STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR
ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE
CONTRARY IS A CRIMINAL OFFENSE.
_______________________________________________________________
Read and retain both parts of this Prospectus for future reference.
Units of the Trust are not deposits or obligations of, or guar-
anteed or endorsed by, any bank, and the Units are not feder-
ally insured by the Federal Deposit Insurance Corporation, Fed-
eral Reserve Board, or any other agency.
Prospectus Part A dated July 31, 1997
<PAGE>
THIS PROSPECTUS DOES NOT CONTAIN ALL OF THE INFORMATION WITH
RESPECT TO THE INVESTMENT COMPANY SET FORTH IN ITS REGISTRATION
STATEMENT AND EXHIBITS RELATING THERETO WHICH HAVE BEEN FILED
WITH THE SECURITIES AND EXCHANGE COMMISSION, WASHINGTON, D.C.,
UNDER THE SECURITIES ACT OF 1933 AND THE INVESTMENT COMPANY ACT
OF 1940, AND TO WHICH REFERENCE IS HEREBY MADE.
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
TABLE OF CONTENTS
Page
PART A
Table of Contents..................................... A-1
Summary of Essential Information...................... A-3
Independent Auditor's Report.......................... F-1
PART B
Introduction.......................................... 1
The Trust............................................. 2
Special Considerations........................... 2
Summary Description of the Portfolios............ 3
Insurance on the Securities in an Insured Trust....... 21
Objectives and Securities Selection................... 25
The Units............................................. 26
Tax Status............................................ 27
Public Offering of Units.............................. 32
Public Offering Price............................ 32
Public Distribution.............................. 33
Secondary Market................................. 34
Profit of Sponsor................................ 35
Volume Discount.................................. 35
Exchange Option....................................... 36
Reinvestment Programs................................. 37
Redemption............................................ 38
Tender of Units.................................. 38
Computation of Redemption Price per Unit......... 39
Purchase by the Sponsor of Units Tendered 39
for Redemption.................................
Rights of Unit Holders................................ 40
Certificates..................................... 40
Certain Limitations.............................. 40
Expenses and Charges.................................. 40
Initial Expenses................................. 40
Fees............................................. 40
Other Charges.................................... 41
A-1
<PAGE>
Page
Administration of the Trust........................... 42
Records and Accounts............................. 42
Distribution..................................... 42
Distribution of Interest and Principal........... 42
Reports to Unit Holders.......................... 44
Sponsor............................................... 45
Trustee............................................... 47
Evaluator............................................. 48
Amendment and Termination of the Indenture............ 49
Legal Opinions........................................ 50
Auditors.............................................. 50
Bond Ratings.......................................... 50
Federal Tax Free vs. Taxable Income................... 54
Sponsor:
Dean Witter Reynolds Inc.
Two World Trade Center
New York, New York 10048
Evaluator:
Kenny S&P Evaluation Services
A Division of J.J. Kenny Co., Inc.
65 Broadway
New York, New York 10006
Trustee:
The Chase Manhattan Bank
270 Park Avenue
New York, New York 10017
NO PERSON IS AUTHORIZED TO GIVE ANY INFORMATION OR TO MAKE ANY
REPRESENTATIONS WITH RESPECT TO THIS INVESTMENT COMPANY NOT
CONTAINED IN THIS PROSPECTUS; AND ANY INFORMATION OR
REPRESENTATION NOT CONTAINED HEREIN MUST NOT BE RELIED UPON AS
HAVING BEEN AUTHORIZED. THIS PROSPECTUS DOES NOT CONSTITUTE AN
OFFER TO SELL, OR A SOLICITATION OF AN OFFER TO BUY, SECURITIES
IN ANY STATE TO ANY PERSON TO WHOM IT IS NOT LAWFUL TO MAKE
SUCH OFFER IN SUCH STATE.
A-2
<PAGE>
<TABLE>
<CAPTION>
SUMMARY OF ESSENTIAL INFORMATION
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
As of May 31, 1997
<S> <C> <S> <C>
FACE AMOUNT OF SECURITIES $3,360.00 DAILY RATE AT WHICH ESTIMATED NET
INTEREST ACCRUES PER UNIT .0170%
NUMBER OF UNITS 3,430
ESTIMATED CURRENT RETURN (based on
Public Offering Price)<F2> 5.857%
FRACTIONAL UNDIVIDED INTEREST IN THE
TRUST REPRESENTED BY EACH UNIT 1/3,430th ESTIMATED LONG TERM RETURN (based on
Public Offering Price)<F2> 4.686%
PUBLIC OFFERING PRICE MONTHLY INTEREST DISTRIBUTIONS
Aggregate bid side evaluation Estimated net annual interest rate
of Securities in the Trust $3,513,408.00 per Unit times $1,000 $61.27
Divided by 12 $ 5.10
Divided by 3,430 Units $ 1,024.32
RECORD DATE: The ninth day of each month
Plus sales charge of 3.253% of
Public Offering Price (3.362% DISTRIBUTION DATE: The fifteenth
of net amount invested in day of each month
Securities) 34.44
MINIMUM PRINCIPAL DISTRIBUTION: No
Public Offering Price per Unit 1,058.76 distribution need be made from the
Principal Account if balance therein
Plus undistributed principal and is less than $1 per Unit outstanding
net investment income and accrued
interest 21.83<F1> TRUSTEE'S ANNUAL FEE AND EXPENSES (includ-
ing estimated expenses and Evaluator's
Adjusted Public Offering Price $ 1,080.59 fee) $2.37 per $1,000 face amount
of underlying Securities $ 2.37
SPONSOR'S REPURCHASE PRICE AND SPONSOR'S ANNUAL PORTFOLIO SUPERVISION FEE:
REDEMPTION PRICE PER UNIT (based Maximum of $.25 per $1,000 face amount
on bid side evaluation of under- of underlying Securities .25
lying Securities, $34.44 less
than Adjusted Public Offering Price TOTAL ESTIMATED ANNUAL EXPENSES PER UNIT $ 2.62
per Unit) $ 1,046.15
EVALUATOR'S FEE FOR EACH EVALUATION: Minimum
CALCULATION OF ESTIMATED NET of $8.00 plus $.25 for each issue of
ANNUAL INTEREST RATE PER UNIT underlying Securities in excess of 50
(based on face amount of $1,000 issues (treating separate maturities as
per Unit) separate issues)
Annual interest rate per Unit 6.389% EVALUATION TIME: 4:00 P.M. New York Time
Less estimated annual expenses per MANDATORY TERMINATION DATE: January 1, 2041
Unit ($2.62) expressed as a
percentage .262% DISCRETIONARY LIQUIDATION AMOUNT: The Trust
may be terminated by the Sponsor if the
Estimated net annual interest rate value of the portfolio of the Trust at
per Unit 6.127% any time is less than $1,510,000.
<F1>Figure shown includes interest accrued (net of expenses) on the underlying Securities to the expected
date of settlement (normally three business days after purchase) for Units purchased on May 30, 1997, the
last trading day during the period.
<F2>The estimated current return and estimated long term return are increased for transactions entitled to a
reduced sales charge. (See "The Units - Estimated Annual Income and Current Return" and "Public Offering of
Units - Volume Discount" in Part B of this Prospectus.)
A-3
</TABLE>
<PAGE>
SUMMARY OF ESSENTIAL INFORMATION
(Continued)
THE TRUST -- The Dean Witter Select Municipal Trust,
Long Term Portfolio Series 120 (the "Trust ") is a unit invest-
ment trust created on June 11, 1992 (the "Date of Deposit"),
under the laws of the State of New York, pursuant to an Inden-
ture as defined in Part B. The Trust is composed of
"investment grade" long-term interest-bearing municipal bonds
(the "Securities"). (For a description of the meaning of
"investment grade" securities, see: "Bond Ratings", in
Part B.) The objectives of the Trust are: (1) the receipt of
income which, under existing law, is excludable from gross in-
come for Federal income tax purposes (except in certain in-
stances depending on the Unit Holders) and (2) the conservation
of capital. The payment of interest and the preservation of
principal of the Trust is dependent on the continuing ability
of the Issuers of the Securities or the bond insurers thereof
to meet their obligations to pay principal and interest on the
Securities. Therefore, there is no guarantee that the objec-
tives of the Trust will be achieved. All of the Securities in
the Trust are obligations of states, or of the counties, mu-
nicipalities or public authorities thereof. Interest on the
Securities, in the opinion of bond counsel or special tax coun-
sel to the Issuers thereof, under existing law, is excludable
from gross income for Federal income tax purposes (except in
certain instances depending on the Unit Holders). (For a dis-
cussion of certain state tax aspects of the Trust see: "Tax
Status" in Part B.
OFFERS TO SELL OR THE SOLICITATION OF ORDERS TO BUY
MAY ONLY BE MADE IN THOSE JURISDICTIONS IN WHICH THE UNITS OF
THE TRUST HAVE BEEN REGISTERED. INVESTORS SHOULD CONTACT
ACCOUNT EXECUTIVES OF THE SPONSOR TO DETERMINE WHETHER THE
UNITS OF THE TRUST HAVE BEEN REGISTERED FOR SALE IN THE STATE
IN WHICH THEY RESIDE.
MONTHLY DISTRIBUTIONS -- Monthly distributions of
principal, premium, if any, and interest received by the Trust
will be made on or shortly after the fifteenth day of each
month to Unit Holders of record on the ninth day of such month.
Alternatively, Unit Holders may elect to have their monthly
distributions reinvested in either of the Reinvestment Programs
of the Sponsor, neither of which are insured. (See:
"Reinvestment Programs", in Part B.)
PUBLIC OFFERING PRICE -- The Public Offering Price
per Unit of the Trust is calculated daily, and is equal to the
aggregate bid side evaluation of the underlying securities, di-
vided by the number of Units outstanding, plus a sales charge
calculated by reference to "Sales Charge/Volume Discount", be-
A-4
<PAGE>
low, plus the per Unit balance in the Interest and Principal
Accounts. Units are offered at the Public Offering Price, plus
accrued interest. (See: "Public Offering of Units", Part B.)
ESTIMATED CURRENT RETURN -- The Estimated Current Re-
turn shows the return based on the Public Offering Price and is
computed by multiplying the estimated net annual interest rate
per Unit (which shows the return based on a $1,000 face amount)
by $1,000 and dividing the result by the Public Offering Price
(not including accrued interest). The net annual interest rate
per Unit will vary with changes in the fees and expenses of the
Trustee, the Sponsor and the Evaluator and with the exchange,
redemption, sale or maturity of the underlying Securities. In
addition, the Public Offering Price will also vary with fluc-
tuations in the bid side evaluation of the underlying Securi-
ties. Therefore, it can be expected that the Estimated Current
Return will fluctuate in the future. (See: "The Units -- Es-
timated Annual Income and Current Return", in Part B.)
MARKET FOR UNITS -- The Sponsor, though not obligated
to do so, intends to maintain a market for the Units based on
the aggregate bid side evaluation of the underlying Securities,
as more fully described in Part B -- "Public Offering of Units
- -- Secondary Market". If such market is not maintained, a Unit
Holder will be able to dispose of its Units through redemption
at prices based on the aggregate bid side evaluation of the un-
derlying Securities. (See: "Redemption", in Part B.) Market
conditions may cause such prices to be greater or less than the
amount paid for Units.
SPECIAL CONSIDERATIONS -- An investment in Units of
the Trust should be made with an understanding of the risks
which an investment in fixed rate long term debt obligations
may entail, including the risk that the value of the Units will
decline with increases in interest rates. The Trust is consid-
ered to be concentrated in Prerefunded/Escrowed to Maturity Se-
curities (44.95% of the aggregate market value of the Trust
Portfolio). (See: "The Trust -- Special Considerations" and
"The Trust -- Summary Description of the Portfolios", in
Part B. See also: "The Trust", herein, for a discussion of
additional risks relating to Units of such Trust.)
OTHER INFORMATION -- The Securities in the Portfolio
of the Trust were chosen in part on the basis of their maturity
dates. A Trust contains obligations maturing in 15 years or
more from the Date of Deposit. The maturity date of the Trust
is January 1, 2041. The average life to maturity (or date of
pre-refunding of a bond) of the Portfolio of Securities therein
is 6.169 years. The latest maturity of a Security in the Trust
is July 1, 2023; and the average life to maturity (or date of
pre-refunding of a bond) of the Portfolio of Securities therein
A-5
<PAGE>
is 5.808 years. The actual maturity date of the Securities
contained in the Trust are shown on the "Schedule of Portfolio
Securities", herein.
The Trustee shall receive annually 75 cents per
$1,000 principal amount of Securities in the Trust for its
services as Trustee. See: "Expenses and Charges", in Part B,
for a description of other fees and charges which may be in-
curred by a Trust.
SALES CHARGE/VOLUME DISCOUNT -- The Public Offering
Price per Unit will be computed by dividing the aggregate of
the bid prices of the Securities in a Trust by the number of
Units outstanding and then adding the appropriate sales charge
described below.
The sales charge will reflect different rates depend-
ing upon the maturities of the various underlying Securities.
The sales charge per Unit in the secondary market (the
"Effective Sales Charge") will be computed by multiplying the
Evaluator's determination of the bid side evaluation of each
Security by a sales charge determined in accordance with the
table set forth below based upon the number of years remaining
to the maturity of each such Security, totalling all such cal-
culations, and dividing this total by the number of Units then
outstanding. In calculating the date of maturity, a Security
will be considered to mature on its stated maturity date un-
less: (a) the Security has been called for redemption or funds
or securities have been placed in escrow to redeem it on an
earlier call date, in which case the call date will be deemed
the date on which such Security matures; or (b) the Security is
subject to a mandatory tender, in which case the mandatory ten-
der date will be deemed the date on which such Security ma-
tures.
(as % of bid (as % of Public
Time to Maturity side evaluation) Offering Price)
Less than six months........ 0% 0%
six months to 1 year........ 0.756% 0.75%
over 1 year to 2 years...... 1.523% 1.50%
over 2 years to 4 years..... 2.564% 2.50%
over 4 years to 8 years..... 3.627% 3.50%
over 8 years to 15 years.... 4.712% 4.50%
over 15 years............... 5.820% 5.50%
A-6
<PAGE>
The Effective Sales Charge per Unit for a sale in the
secondary market, as determined above, will be reduced on a
graduated scale for sales to any single purchaser on a single
day of the specified number of Units of a Trust set forth be-
low.
Dealer Concession
% of Effective as % of Effective
Number of Units Sales Charge Sales Charge
1-99............... 100% 65%
100-249............ 95% 62%
250-499............ 85% 55%
500-999............ 70% 45%
1,000 or more...... 55% 35%
To qualify for the reduced sales charge and conces-
sion applicable to quantity purchases, the selling dealer must
confirm that the sale is to a single purchaser, as described in
"Volume Discount" in Part B of the Prospectus.
Units purchased at an Effective Sales Charge (before
volume purchase discount) of less than 3.00% of the Public Of-
fering Price (3.093% of the bid side evaluation of the Securi-
ties) will not be eligible for exchange at a reduced sales
charge described under the Exchange Option.
Dealers purchasing certain dollar amounts of Units
during the life of the Trust may be entitled to additional con-
cessions. The Sponsor reserves the right, at any time and from
time to time, to change the level of dealer concessions.
For further information regarding the volume dis-
count, see: "Public Offering of Units -- Volume Discount", in
Part B.
Note: "Auditors" in Part B is amended so that
"Deloitte & Touche" is replaced with "Deloitte & Touche LLP",
and "Evaluator" in Part B is amended so that "Kenny S&P Evalua-
tion Services, a division of Kenny Information Systems, Inc."
is replaced with "Kenny S&P Evaluation Services, a Division of
J.J. Kenny Co., Inc.", and "Trustee" in Part B is amended so
that "United States Trust Company of New York, with its princi-
pal place of business at 114 West 47th Street, New York, New
York 10036, and its unit investment trust office at 770 Broad-
way, New York, New York 10003" is replaced with "The Chase Man-
hattan Bank, a New York Bank with its principal executive of-
fice located at 270 Park Avenue, New York, New York 10017 and
its unit investment trust office at 4 New York Plaza, New York,
A-7
<PAGE>
New York 10004". The reference to the fifth and five business
day in "Redemption -- Computation of Redemption Price per Unit"
and "Administration of the Trust -- Distribution of Interest
and Principal" in Part B is amended to read third and three,
respectively.
On May 31, 1997, Dean Witter, Discover & Co., Dean
Witter's former parent company, and Morgan Stanley Group Inc.
merged to form MCDWD. In connection with such merger, the cor-
porate name or DWDC was changed to Morgan Stanley, Dean Witter,
Discover & Co. ("MCDWD").
On December 20, 1995, Capital Guaranty Corporation
merged with a subsidiary of Financial Security Assurance Hold-
ings Ltd. In connection with such merger, (i) CGIC, the prin-
cipal operating subsidiary of Capital Guaranty Corporation, be-
came a wholly-owned subsidiary of FSA, the principal operating
subsidiary of Financial Security Assurance Holdings Ltd., and
(ii) the corporate name of CGIC was changed to Financial Secu-
rity Assurance of Maryland Inc.
SPECIAL CHARACTERISTICS OF THE TRUST _ The Portfolio
of the Trust consists of eleven issues of Securities, which
were issued by Issuers located in nine states. None of the
issues of Securities is a general obligation of an Issuer. All
issues of Securities, while not backed by the taxing power of
the Issuer, are payable from revenues or receipts derived from
specific projects or other available sources. The Trust con-
tains the following categories of Securities:
A-8
<PAGE>
Percentage of Aggregate
Market Value of Trust Portfolio
Category of Security (as of July 16,1997)
Electric and Power................. 12.72%
Health Care and Hospital........... 10.67%
Housing............................ 23.24%
Sales Tax.......................... 8.42%
State Budget Appropriationa........ .0%
Prerefunded/Escrowed to Maturity... 44.95%
Original Issue Discount............ 43.98%
See: "The Trust -- Summary Description of the Port-
folios", in Part B, for a summary of the investment risks asso-
ciated with the type of Securities contained in the Trust .
See: "Tax Status", in Part B, for a discussion of certain tax
considerations with regard to Original Issue Discount.
Of the Original Issue Discount bonds in the Trust,
approximately 4.62% of the aggregate principal amount of the
Securities in the Trust (or 1.26% of the market value of all
Securities in the Trust on July 16, 1997) are zero coupon bonds
(including bonds known as multiplier bonds, money multiplier
bonds, capital accumulator bonds, compound interest bonds and
discount maturity payment bonds).
Securities representing approximately 7.32% of the
aggregate market value of the Portfolio are currently subject
to redemption from mandatory sinking fund payments. Securities
representing approximately 7.32% of the aggregate market value
of the Portfolio are subject to redemption from mandatory sink-
ing fund payments beginning in 1997. Securities representing
approximately 7.32% of the aggregate market value of the Port-
folio are subject to redemption at the option of the Issuer
thereof beginning in 2000. (See: Schedule of Portfolio Securi-
ties," herein, and "The Trust _ Summary Description of the
Portfolios _ Additional Securities Considerations _ Redemption
of Securities," in Part B.)
a The bonds in this category are issued by various state
agencies and authorities and are payable from amounts to
be appropriated by the state legislature from available
state revenue.
A-9
<PAGE>
On July 16, 1997 based on the bid side of the market,
the aggregate market value of the Securities in the Trust was
$3,432,540.60.
On July 16, 1997, Standard & Poor's Corporation rated
nine of the Securities in the Trust as follows: 24.31%-AAA,
27.33%-AA, 19.96%-A and 12.72%-BBB; and Moody's Investors Serv-
ice rated two of the Securities as follows: 4.04%-Aaa and
11.64%-Aa. (See: the "Schedule of Portfolio Securities",
herein, and "Bond Ratings", in Part B.) A Security in the
Portfolio may subsequently cease to be rated or the rating as-
signed may be reduced below the minimum requirements of the
Trust for the acquisition of Securities. While such events may
be considered by the Sponsor in determining whether to direct
the Trustee to dispose of the Security (see: "Sponsor -- Re-
sponsibility", in Part B), such events do not automatically re-
quire the elimination of such Security from the Portfolio.
A-10
<PAGE>
<AUDIT-REPORT>
INDEPENDENT AUDITORS' REPORT
THE UNIT HOLDERS, SPONSOR AND TRUSTEE
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
We have audited the statement of financial condition and schedule of
portfolio securities of the Dean Witter Select Municipal Trust Long Term
Portfolio Series 120 as of May 31, 1997, and the related statements of
operations and changes in net assets for each of the three years in the
period then ended. These financial statements are the responsibility of the
Trustee (see Footnote (a)(1)). Our responsibility is to express an opinion
on these financial statements based on our audits.
We conducted our audits in accordance with generally accepted auditing
standards. Those standards 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.
Our procedures included confirmation of the securities owned as of May 31,
1997 as shown in the statement of financial condition and schedule of
portfolio securities by correspondence with The Chase Manhattan Bank, the
Trustee. An audit also includes assessing the accounting principles used
and the significant estimates made by the Trustee, as well as evaluating the
overall financial statement presentation. We believe that our audits
provide a reasonable basis for our opinion.
In our opinion, the financial statements referred to above present fairly,
in all material respects, the financial position of the Dean Witter Select
Municipal Trust Long Term Portfolio Series 120 as of May 31, 1997, and the
results of its operations and the changes in its net assets for each of the
three years in the period then ended in conformity with generally accepted
accounting principles.
DELOITTE & TOUCHE LLP
July 7, 1997
New York, New York
F-1
</AUDIT-REPORT>
<PAGE>
STATEMENT OF FINANCIAL CONDITION
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
May 31, 1997
TRUST PROPERTY
Investments in municipal bonds at market value
(amortized cost $3,266,146) (Note (a) and
Schedule of Portfolio Securities Notes (4) and (5)) $3,513,408
Accrued interest receivable 83,086
Total 3,596,494
LIABILITIES AND NET ASSETS
Less Liabilities:
Cash overdraft 700
Accrued Trustee's fees and expenses 7,435
Accrued Sponsor's fees 1,834
Total liabilities 9,969
Net Assets:
Balance applicable to 3,430 Units of fractional
undivided interest outstanding (Note (c)):
Capital, plus net unrealized market appreci-
ation of $247,262 $3,513,408
Undistributed principal and net investment
income (Note (b)) 73,117
Net assets $3,586,525
Net asset value per Unit ($3,586,525 divided by 3,430 Units) $ 1,045.63
See notes to financial statements
F-2
<PAGE>
STATEMENTS OF OPERATIONS
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
For the years ended May 31,
1997 1996 1995
Investment income - interest $234,169 $240,126 $243,369
Less Expenses:
Trustee's fees and expenses 8,353 8,564 8,675
Sponsor's fees 881 903 915
Total expenses 9,234 9,467 9,590
Investment income - net 224,935 230,659 233,779
Net gain (loss) on investments:
Realized gain (loss) on securities sold
or redeemed 10,224 3,376 (2,802)
Net unrealized market appreciation
(depreciation) 30,660 (30,732) 92,042
Net gain (loss) on investments 40,884 (27,356) 89,240
Net increase in net assets resulting from
operations $265,819 $203,303 $323,019
See notes to financial statements
F-3
<PAGE>
STATEMENTS OF CHANGES IN NET ASSETS
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
For the years ended May 31,
1997 1996 1995
Operations:
Investment income - net $ 224,935 $ 230,659 $ 233,779
Realized gain (loss) on securities
sold or redeemed 10,224 3,376 (2,802)
Net unrealized market appreciation
(depreciation) 30,660 (30,732) 92,042
Net increase in net assets
resulting from operations 265,819 203,303 323,019
Less Distributions to Unit Holders:
Investment income - net (221,706) (227,481) (230,619)
Total distributions (221,706) (227,481) (230,619)
Less Capital Share Transactions:
Redemption of 241 Units, 35 Units
and 69 Units, respectively (246,836) (36,222) (65,607)
Accrued interest on redemption (5,344) (811) (1,487)
Total capital share
transactions (252,180) (37,033) (67,094)
Net (decrease) increase in net assets (208,067) (61,211) 25,306
Net assets:
Beginning of year 3,794,592 3,855,803 3,830,497
End of year (including undistributed
principal and net investment in-
come of $73,117, $77,811 and
$75,961, respectively) $3,586,525 $3,794,592 $3,855,803
See notes to financial statements
F-4
<PAGE>
NOTES TO FINANCIAL STATEMENTS
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
May 31, 1997
(a) SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
The Trust is registered under the Investment Company Act of 1940 as a
Unit Investment Trust. The following is a summary of the significant
accounting policies of the Trust:
(1) Basis of Presentation
The Trustee has custody of and responsibility for all accounting and
financial books, records, financial statements and related data of
the Trust and is responsible for establishing and maintaining a
system of internal controls directly related to, and designed to
provide reasonable assurance as to the integrity and reliability
of, financial reporting of the Trust. The Trustee is also
responsible for all estimates and accruals reflected in the Trust's
financial statements. The Evaluator determines the price for each
underlying Security included in the Trust's Portfolio of Securities
on the basis set forth in Part B of this Prospectus, "Public
Offering of Units - Public Offering Price". Under the Securities
Act of 1933 ("the Act"), as amended, the Sponsor is deemed to be an
issuer of the Trust Units. As such, the Sponsor has the
responsibility of an issuer under the Act with respect to financial
statements of the Trust included in the Trust's Registration
Statement under the Act and amendments thereto.
(2) Investments
Investments are stated at market value as determined by the
Evaluator based on the bid side evaluations on the last day of
trading during the period, except that value on the date of deposit
(June 11, 1992) represents the cost of investments to the Trust
based on the offering side evaluations as of the day prior to the
date of deposit.
(3) Income Taxes
The Trust is not an association taxable as a corporation for Federal
income tax purposes; accordingly, no provision is required for such
taxes.
(4) Expenses
The Trust pays annual Trustee's fees, including estimated expenses
and Evaluator's fees and annual Sponsor's portfolio supervision
fees and may incur additional charges as explained under "Expenses
and Charges - Fees" and "- Other Charges" in Part B of this
Prospectus.
F-5
<PAGE>
NOTES TO FINANCIAL STATEMENTS
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
May 31, 1997
(b) DISTRIBUTIONS
Interest received by the Trust is distributed to the Unit Holders on or
shortly after the fifteenth day of each month after deducting applicable
expenses. Receipts other than interest are distributed as explained in
"Administration of the Trust - Distribution of Interest and Principal"
in Part B of this Prospectus.
(c) ORIGINAL COST TO INVESTORS
The original cost to investors represents the aggregate initial public
offering price as of the date of deposit (June 11, 1992) exclusive of
accrued interest, computed on the basis set forth under "Public Offering
of Units - Public Offering Price" in Part B of this Prospectus.
A reconciliation of the original cost of Units to investors to the net
amount applicable to investors as of May 31, 1997 follows:
Original cost to investors $3,869,989
Less: Gross underwriting commissions (sales charge) (189,613)
Net cost to investors 3,680,376
Cost of securities sold or redeemed (427,275)
Net unrealized market appreciation 247,262
Accumulated interest accretion 13,045
Net amount applicable to investors $3,513,408
(d) OTHER INFORMATION
Selected data for a Unit of the Trust during each year:
For the years ended May 31,
1997 1996 1995
Net investment income distribu-
tions during year $ 61.45 $ 61.62 $ 61.56
Net asset value at end of year $1,045.63 $1,033.67 $1,040.42
Trust Units outstanding at end
of year 3,430 3,671 3,706
F-6
<PAGE>
<TABLE>
<CAPTION>
SCHEDULE OF PORTFOLIO SECURITIES
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
May 31, 1997
Port- Optional
folio Rating Face Coupon Maturity Sinking Fund Refunding Market
No. Title of Securities <F3> Amount Rate Date Redemptions<F5> Redemptions<F4> Value<F6><F7>
<S><C> <C> <C> <C> <C> <C> <C> <C>
1. Wilmington, Delaware,
Single-Family Residual Reve-
nue Zero Coupon Bonds,
Series 1990C <F8> AA+ $ 150,000 0.000% 07/25/14 NONE NONE $ 42,494
2. Metropolitan Pier and Ex-
position Authority, Illi-
nois Dedicated State Tax
Revenue Bonds, Series 1992 A+ 250,000 6.750 06/01/10 06/01/08@100 NONE 280,990
3. Highland School Building
Corporation, First Mortgage
Bonds, Series 1992A
(Refunded) <F10> AAA 400,000 6.750 07/15/12 NONE 01/15/02@102 441,036
4. Indiana Health Facility
Financing Authority, Hospi-
tal Revenue Bonds, Series
1992 (Floyd Memorial Hospi-
tal Project) A 345,000 6.625 02/15/13 02/15/08@100 02/15/02@102 360,905
5. Michigan Housing Develop-
ment Authority, Single-
Family Mortgage Revenue
Bonds, 1992 Series A <F8> AA+ 335,000 6.800 12/01/12 06/01/10@100 06/01/02@102 351,700
6. New York Local Government
Assistance Corporation,
Series 1991D Bonds
(Refunded) <F10> AAA 345,000 6.750 04/01/21 NONE 04/01/02@102 382,346
7. North Dakota Housing
Finance Agency, Single-
Family Mortgage Program
Bonds, 1992 Series A <F8> Aa2<F9> 380,000 6.800 07/01/23 07/01/17@100 01/01/02@102 396,104
8. Pennsylvania Intergovern-
mental Cooperation Author-
ity, Special Tax Revenue
Bonds, (Philadelphia Fund-
ing Program), Series of 1992
(Refunded) <F10> Aaa<F9> 125,000 6.800 06/15/22 NONE 06/15/02@100 136,951
9. Washington Health Care
Facilities Authority Revenue
Bonds, Series 1989 (Sisters
of Providence) (Refunded)
<F10> AA- 230,000 7.875 10/01/10 Currently@100 10/01/99@102 248,034
10. Mason County, West Vir-
ginia, Pollution Control
Revenue Bonds, (Appalachian
Power Company Project),
Series I BBB+ 400,000 6.850 06/01/22 NONE 06/01/02@102 432,268
11. West Virginia School
Building Authority, Capital
Improvement Revenue Bonds,
Series 1992A (Refunded) <F10> A 400,000 6.625 07/01/22 NONE 07/01/02@102 440,580
$3,360,000 $3,513,408
See notes to schedule of portfolio securities
</TABLE> F-7
<PAGE>
NOTES TO SCHEDULE OF PORTFOLIO SECURITIES
DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES 120
May 31, 1997
<F3> All ratings are provided by Standard & Poor's Corporation, unless
otherwise indicated. A brief description of applicable Security
ratings is given under "Bond Ratings" in Part B of this Prospectus.
<F4> There is shown under this heading the date on which each issue of
Securities is redeemable by the operation of optional call
provisions and the redemption price for that date; unless otherwise
indicated, each issue continues to be redeemable at declining
prices thereafter but not below par. Securities listed as non-
callable, as well as Securities listed as callable, may also be
redeemable at par under certain circumstances from special
redemption payments.
<F5> There is shown under this heading the date on which an issue of
Securities is subject to scheduled sinking fund redemption and the
redemption price on such date.
<F6> The market value of the Securities as of May 31, 1997 was determined
by the Evaluator on the basis of bid side evaluations for the
Securities on the last trading date during the period (May 30,
1997).
<F7> At May 31, 1997, the net unrealized market appreciation of all
Securities was comprised of the following:
Gross unrealized market appreciation $249,181
Gross unrealized market depreciation (1,919)
Net unrealized market appreciation $247,262
The amortized cost of the Securities for Federal income tax purposes
was $3,266,146 at May 31, 1997.
<F8> See "The Trust - Summary Description of the Portfolios - Revenue
Securities - Housing Securities" in Part B of this Prospectus for
the discussion relating to Housing Securities.
<F9> Moody's Investors Service, Inc. rating.
<F10> The Issuer has indicated that it will refund this Security on its
optional redemption date.
F-8
<PAGE>
(MODULE)
(NAME) DWSMTPARTB941
(CIK) 0000840581
(CCC) uit*59fl
(/MODULE)
<PAGE>
CONTENTS OF REGISTRATION STATEMENT
This registration statement comprises the following docu-
ments:
The facing sheet.
The Cross Reference Sheet.
The Prospectus.
The signatures.
Consents of the Evaluator and Independent Auditors; all
other consents were previously filed.
The following exhibits:
23. 1a. Consents of Kenny S&P Evaluation Services, a di-
vision of J.J. Kenny Co., Inc.
1b. Consent of Independent Auditors.
27.1. Financial Data Schedule
<PAGE>
CONSENT OF COUNSEL
The consent of Counsel to the use of its name in the
Prospectus included in this Registration Statement is contained
in its opinion filed as Exhibit 3 to this Registration State-
ment.
<PAGE>
SIGNATURES
Pursuant to the requirements of the Securities Act of
1933, the registrant, Dean Witter Select Municipal Trust, Long
Term Portfolio Series 120, certifies that it meets all of the
requirements for effectiveness of this Registration Statement
pursuant to Rule 485(b) under the Securities Act of 1933 and
has duly caused this Post-Effective Amendment No. 5 to the Reg-
istration Statement to be signed on their behalf by the under-
signed, thereunto duly authorized, all in The City of New York
and State of New York on the 31st day of July, 1997.
DEAN WITTER SELECT MUNICIPAL TRUST,
LONG TERM PORTFOLIO SERIES 120
(Registrants)
By: DEAN WITTER REYNOLDS INC.
(Depositor)
Thomas Hines
------------------
Thomas Hines
Authorized Signatory
Pursuant to the requirements of the Securities Act of
1933, this Post-Effective Amendment No. 5 to the Registration
Statement has been signed on behalf of Dean Witter Reynolds
Inc., the Depositor, by the following person in the following
capacities and by the following persons who constitute a major-
ity of the Depositor's Board of Directors in The City of New
York and State of New York on this 31st day of July, 1997.
DEAN WITTER REYNOLDS INC.
Name Office
Philip J. Purcell Chairman and Chief )
Executive Officer )
and Directora )
By:___________________
Thomas Hines
Thomas Hines
Attorney-in-fact*
- -------------
* Executed copies of the Powers of Attorney filed by a ma-
jority of the Board of Directors of Dean Witter Reynolds
Inc. have been previously filed.
<PAGE>
Name Office
Richard M. DeMartini Director***
Robert J. Dwyer Director***
Christine A. Edwards Director***
James F. Higgins Director***
Charles A. Fiumefreddo Director**
Mitchell M. Merin Director*
Stephen R. Miller Director**
Richard F. Powers III Director*
Philip J. Purcell Director***
Thomas C. Schneider Director**
William B. Smith Director**
____________________
* Executed copies of the Powers of Attorney have been filed
with the Securities and Exchange Commission in connection
with Amendment No. 1 to the Registration Statement on
Form S-6 for Dean Witter Select Equity Trust, Select 10
Industrial Portfolio '97-1, File No. 333-16839.
** Executed copies of Powers of Attorney have been filed with
the Securities and Exchange Commission in connection with
Amendment No. 1 to the Registration Statment on Form S-6
for Dean Witter Select Equity Trust, Select 10 Industrial
Portfolio 96-4, File No. 333-10499.
*** Executed copies of Powers of Attorney have been filed with
the Securities and Exchange Commission in connection with
the Registration Statement on Form S-6 for Dean Witter
Select Equity Trust, Select 10 International Series 95-1,
File No. 33-56389.
<PAGE>
<PAGE>
EXHIBIT INDEX
EXHIBIT NO. TITLE OF DOCUMENT
23. 1a. Consents of Kenny S&P Evaluation Services,
a division of J.J. Kenny Co., Inc.
1b. Consent of Deloitte & Touche LLP
27. 1. Financial Data Schedule
<PAGE>
Letterhead of KENNY S&P EVALUATION SERVICES
A division of J.J. Kenny Co., Inc.
July 31, 1997
Dean Witter Reynolds Inc.
Two World Trade Center
New York, NY 10048
Re: Dean Witter Select Municipal Trust,
Long Term Portfolio Series 120
Gentlemen:
We have examined the post-effective Amendment to the
Registration Statement File No. 33-28194 for the above- cap-
tioned trust. We hereby acknowledge that Kenny S&P Evaluation
Services, a division of J.J. Kenny Co., Inc. is currently act-
ing as the evaluator for the trust. We hereby consent to the
use in the Amendment of the reference to Kenny S&P Evaluation
Services, a division of J.J. Kenny Co., Inc. as evaluator.
In addition, we hereby confirm that the ratings indi-
cated in the above-referenced Amendment to the Registration
Statement for the bonds comprising the trust portfolio are the
ratings currently indicated in our KENNYBASE database as of the
evaluation report.
You are hereby authorized to file a copy of this let-
ter with the Securities and Exchange Commission.
Sincerely,
Frank A. Ciccotto
Frank A. Ciccotto
<PAGE>
Exhibit 23.lb.
CONSENT OF INDEPENDENT AUDITORS
We consent to the use of our report dated July 7, 1997, accompanying the
financial statements of the Dean Witter Select Municipal Trust Long Term
Portfolio Series 120 included herein and to the reference to our Firm as
experts under the heading "Auditors" in the prospectus which is a part of
this registration statement.
DELOITTE & TOUCHE LLP
July 31,1997
New York, New York
<TABLE> <S> <C>
<PAGE>
<ARTICLE> 6
<LEGEND> THE SCHEDULE CONTAINS SUMMARY FINANCIAL
INFORMATION EXTRACTED FROM THE FINANCIAL
STATEMENTS FOR DEAN WITTER SELECT
MUNICIPAL TRUST LONG TERM PORTFOLIO SER
IES 120 AND IS QUALIFIED IN ITS ENTIRETY
BY REFERENCE TO SUCH FINANCIAL
STATEMENTS
<RESTATED>
<SERIES>
<NAME> DEAN WITTER SELECT MUNICIPAL TRUST
LONG TERM PORTFOLIO SERIES
<NUMBER> 120
<MULTIPLIER> 1
<FISCAL-YEAR-END> May-31-1997
<PERIOD-START> Jun-1-1996
<PERIOD-END> May-31-1997
<PERIOD-TYPE> YEAR
<INVESTMENTS-AT-COST> 3,266,146
<INVESTMENTS-AT-VALUE> 3,513,408
<RECEIVABLES> 83,086
<ASSETS-OTHER> 0
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 3,596,494
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 9,969
<TOTAL-LIABILITIES> 9,969
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 3,265,960
<SHARES-COMMON-STOCK> 3,430
<SHARES-COMMON-PRIOR> 3,671
<ACCUMULATED-NII-CURRENT> 73,303
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 247,262
<NET-ASSETS> 3,586,525
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 231,185
<OTHER-INCOME> 2,984
<EXPENSES-NET> 9,234
<NET-INVESTMENT-INCOME> 224,935
<REALIZED-GAINS-CURRENT> 10,224
<APPREC-INCREASE-CURRENT> 30,660
<NET-CHANGE-FROM-OPS> 265,819
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 221,706
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> 241
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> (208,067)
<ACCUMULATED-NII-PRIOR> 78,402
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 0
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 0
<AVERAGE-NET-ASSETS> 0
<PER-SHARE-NAV-BEGIN> 0
<PER-SHARE-NII> 0
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 0
<EXPENSE-RATIO> 0
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
