


                       [Letterhead of Brown & Wood LLP]


                                                                     Exhibit 5

                                                           June 2, 1997


Morgan Stanley, Dean Witter, Discover & Co.
1585 Broadway
New York, NY  10036

Ladies and Gentlemen:

      We have acted as counsel to Morgan Stanley, Dean Witter, Discover & Co.,
a Delaware corporation (the "Company"), in connection with the preparation and
filing of a registration statement on Form S-3 (as it may be amended or
supplemented from time to time, the "Registration Statement") under the
Securities Act of 1933, as amended (the "Securities Act"), with respect to
$7,000,000,000 aggregate initial offering price of the following securities
(collectively, the "Securities"): (i) debt securities ("Debt Securities"),
(ii)  warrants to purchase Debt Securities ("Debt Warrants") or to purchase
or sell (a) securities of an entity unaffiliated with the Company, a basket
of such securities, an index of indices of such securities or any
combination of the above, (b) currencies or composite currencies or (c)
commodities ("Universal Warrants," and together with Debt Warrants, the
"Warrants"), (iii) purchase contracts ("Purchase Contracts") requiring the
holders thereof to purchase or sell (a) securities of an entity unaffiliated
with the Company, a basket of such securities, an index or indices of such
securities or any combination of the above, (b) currencies or composite
currencies or (c) commodities, (iv) Debt Securities, Purchase Contracts and
Warrants or any combination thereof that may be offered in the form of
Units ("Units"), (v) shares of the Company's preferred stock, par value
$0.01 per share ("Preferred Stock"), to be issued from time to time in one
or more series and (vi) an indeterminate number of depositary shares
representing fractional interests in shares of the Preferred Stock (the
"Depositary Shares").

      The Debt Securities and certain pre-paid Purchase Contracts
("Pre-paid Purchase Contracts"), if any, are to be issued from time to time
as either (a) senior indebtedness of the Company under an indenture dated
as of April 15, 1989, as supplemented by a First Supplemental Senior
Indenture dated as of May 15, 1991 and a Second Supplemental Senior
Indenture dated as of April 15, 1996, between Morgan Stanley Group Inc.
("Morgan Stanley") and The Chase Manhattan Bank (formerly known as Chemical
Bank), as trustee (the "Senior Debt Trustee"), and a Third Supplemental
Senior Indenture dated as of June 1, 1997 (the "Third Supplemental Senior
Indenture") between the Company (as successor to Morgan Stanley) and the
Senior Debt Trustee (such indenture as so supplemented the "Senior
Indenture") or (b) subordinated indebtedness of the Company under an
indenture dated as of April 15, 1989, as supplemented by a First
Supplemental Subordinated Indenture dated as of May 15, 1991 and a Second
Supplemental Subordinated Indenture dated as of April 15, 1996, between
Morgan Stanley and The First National Bank of Chicago, as trustee (the
"Subordinated Debt Trustee"), and a Third Supplemental Subordinated
Indenture dated as of June 1, 1997 (the "Third Supplemental Subordinated
Indenture" and, together with the Third Supplemental Senior Indenture, the
"Third Supplemental Indentures") between the Company (as successor to
Morgan Stanley) and the Subordinated Debt Trustee (such indenture as so
supplemented the "Subordinated Indenture" and, together with the Senior
Indenture, the "Indentures").  The Debt Warrants, if any, will be issued
under a debt warrant agreement to be entered into between the Company and a
debt warrant agent (the "Debt Warrant Agreement").  The Universal Warrants,
if any, will be issued under a universal warrant agreement to be entered
into between the Company and The Chase Manhattan Bank, as warrant agent
(the "Universal Warrant Agreement").  The Purchase Contracts and Units, if
any, will be issued under a unit agreement to be entered into among the
Company, The Chase Manhattan Bank as unit agent and the holders from time
to time of the Units (the "Unit Agreement").  Depositary Shares
representing fractional interests in shares of Preferred Stock will be
issued under a preferred stock deposit agreement to be entered into among
the Company, The Bank of New York, as depositary, and the holders from time
to time of depositary receipts issued thereunder (the "Deposit Agreement").
The forms of the Indentures, the Debt Warrant Agreement, the Deposit
Agreement and the Securities are filed or incorporated by reference as
exhibits to the Registration Statement.

      In rendering this opinion, we have examined the originals or copies,
certified to our satisfaction, of such corporate records and other documents
and certificates as we deemed necessary.  In such examination, we have assumed
the genuineness of all signatures, the authenticity of all documents submitted
to us as originals, the conformity to the original documents of all documents
submitted to us as copies and the authenticity of the originals of all such
latter documents.  In addition, in rendering this opinion, we have assumed the
authorization, execution and delivery of the Indentures, the Debt Warrant
Agreement and the Deposit Agreement by all parties (including Morgan Stanley)
other than the Company.  As to any facts material to this opinion, we have,
when relevant facts were not independently established by us, relied upon the
aforesaid records, certificates and documents.

      Based upon the foregoing, and having regard for such legal
considerations as we have deemed relevant, we are of the opinion that:

      (i) the Third Supplemental Indentures, the Debt Warrant Agreement, the
Universal Warrant Agreement, the Unit Agreement, the Deposit Agreement and
the Securities have been duly authorized by the Company;

      (ii) when the Debt Warrant Agreement, the Universal Warrant Agreement
and the Unit Agreement have been duly executed and delivered by the Company
and the Debt Securities, the  Debt Warrants, the Universal Warrants, the
Purchase Contracts and the Units have been duly executed and issued in
accordance with the provisions of the applicable Indenture and the Debt
Warrant Agreement, the Universal Warrant Agreement and the Unit Agreement,
respectively, and duly paid for by the purchasers thereof in the manner and
on the terms described in the Registration Statement (after it is declared
effective), all required corporate action will have been taken with respect
to the issuance and sale of the Debt Securities, the Debt Warrants, the
Universal Warrants, the Purchase Contracts and the Units and such
Securities will have been validly issued and will constitute valid and
binding obligations of the Company, enforceable in accordance with their
terms; and

      (iii) when the shares of Preferred Stock and, if applicable, the
Depositary Shares have been duly issued and paid for by the purchasers thereof
in the manner and on the terms described in the Registration Statement (after
it is declared effective), such shares of Preferred Stock will be duly and
validly issued, fully paid and nonassessable and, if applicable, such
Depositary Shares will represent legal and valid interests in the corresponding
shares of Preferred Stock.

      The opinions set forth herein are limited to matters of the laws of the
State of New York and the General Corporation Law of the State of Delaware.
Any opinion expressed herein as to enforceability is qualified in that such
enforceability may be limited by bankruptcy, insolvency, reorganization,
liquidation, moratorium and other similar laws affecting creditors' rights
generally and is subject to general principles of equity, regardless of
whether such enforceability is considered in a proceeding in equity or at law.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm appearing under the
caption "Legal Matters" in the related Prospectus.  In giving such consent, we
do not thereby admit that we are in the category of persons whose consent is
required under Section 7 of the Securities Act.


                                                      Very truly yours,


                                                       /s/ Brown & Wood LLP

