PROSPECTUS Dated March 26, 1998 Pricing Supplement No. 66 to
PROSPECTUS SUPPLEMENT Registration Statement No. 333-46935
Dated March 26, 1998 April 1, 1999
Rule 424(b)(3)
Morgan Stanley Dean Witter & Co.
MEDIUM-TERM NOTES, SERIES C
Senior Floating Rate Notes
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We will not redeem these Medium-Term Notes, Series C (Senior
Floating Rate Notes) prior to the Maturity Date. We describe the basic
features of this type of note in the section called "Description of
Notes--Floating Rate Notes" in the accompanying Prospectus Supplement, subject
to and as modified by the provisions described below.
The Internal Revenue Service Restructuring and Reform Act of
1998 eliminated the 18-month holding period requirement for certain individual
taxpayers to qualify for the lowest tax rate for capital gain. The minimum
holding period required to qualify for the lowest tax rate currently is 12
months. In addition, the effective date of the New Regulations (as defined in
"United States Federal Taxation -- Backup Withholding" in the accompanying
Prospectus Supplement) has been changed so that the New Regulations will apply
to payments made after December 31, 1999.
Principal Amount: $25,000,000
Maturity Date: April 8, 2002
Interest Accrual Date: April 7, 1999
Interest Payment Dates: Each January 8, April 8, July 8 and October 8,
commencing July 8, 1999
Initial Interest Rate: To be determined two London Banking Days prior to
the date of issuance
Base Rate: LIBOR
Index Maturity: 3 Months
Spread (Plus or Minus): Plus 0.17% per annum
Index Currency: U.S. Dollars
Interest Payment
Period: Quarterly
Specified Currency: U.S. Dollars
Issue Price: 100%
Settlement Date
(Original Issue Date): April 7, 1999
Initial Interest Reset
Date: July 8, 1999
Interest Reset Dates: Same as Interest Payment Dates
Interest Reset Period: Quarterly
Interest Determination
Dates: Two London Banking Days prior to each
Interest Reset Date
Reporting Service: Telerate (Page 3750)
Book Entry Note or
Certificated Note: Book Entry Note
Senior Note or
Subordinated Note: Senior Note
Agent: Morgan Stanley & Co. Incorporated
Calculation Agent: The Chase Manhattan Bank
Minimum Denomination: $1,000
CUSIP: 61745ENG2
Capitalized terms not defined above have the meanings given to such terms in
the accompanying Prospectus Supplement.
MORGAN STANLEY DEAN WITTER
