EXHIBIT 5-a


                    [Letterhead of Brown & Wood LLP]

                                                            February 12, 1998


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


          Re:  Morgan Stanley, Dean Witter, Discover & Co.
               MSDW Capital Trust I, MSDW Capital Trust II,
               MSDW Capital Trust III, MSDW Capital Trust IV
               and MSDW Capital Trust V
               Registration Statement on Form S-3
               ----------------------------------

Ladies and Gentlemen:


     We have acted as counsel to Morgan Stanley, Dean Witter, Discover & Co.,
a Delaware corporation (the "Company") and depositor of MSDW Capital Trust I,
MSDW Capital Trust II, MSDW Capital Trust III, MSDW Capital Trust IV and MSDW
Capital Trust V, each a statutory business trust formed under the laws of the
State  of Delaware  (each, an  "Issuer Trust"  and, collectively,  the Issuer
Trusts),  in  connection  with a  Registration  Statement  (the "Registration
Statement") on  Form S-3 filed  by the Company and  the Issuer Trusts  on the
date  hereof with  the Securities  and  Exchange Commission  pursuant to  the
Securities Act of  1933, as amended  (the "Securities Act"), relating  to the
registration  of Debt  Securities  of the  Company  (the "Debt  Securities"),
Capital  Securities  of  the Issuer  Trusts  (the  "Capital Securities")  and
Guarantees  of  the Company  with  respect  to  the Capital  Securities  (the
"Guarantees").  

     The Debt Securities  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"), (b) senior 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, be-
tween Morgan Stanley and The First National Bank of Chicago, as  trustee (the
"Senior 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  Senior Subordinated  Debt Trustee  (such indenture as  so
supplemented, the "Senior Subordinated Indenture") or (c) junior subordinated
indebtedness  of the Company  under an indenture  to be entered  into between
the Company  and  The Bank of New York,  as trustee (the "Junior Subordinated
Indenture"   and,  together   with   the  Senior  Indenture  and  the  Senior
Subordinated Indenture, the "Indentures").  

     The Capital Securities of  each Issuer Trust will be  issued pursuant an
Amended and Restated  Trust Agreement (the "Trust Agreement")  of such Issuer
Trust to  be entered  into among  the Company,  as depositor  of such  Issuer
Trust, The  Bank of  New York,  as property  trustee,  The Bank  of New  York
(Delaware), as Delaware  trustee, two individuals selected by  the holders of
the  Common Securities  issued by  such Issuer  Trust as  administrators with
respect to such Issuer Trust and the holders of the Common Securities and the
Capital Securities of such Issuer Trust.

     The forms  of the Indentures,  the Trust Agreements, the  Guarantees and
the Debt 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
Trust Agreements and the Guarantees 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  Junior   Subordinated
Indenture, the Debt  Securities and the Guarantees have  been duly authorized
by the Company;

     (ii) when  a  Debt  Security  has  been  duly  executed  and  issued  in
accordance with the provisions of the applicable Indenture, and duly paid for
by the purchaser  thereof in the  manner and  on the terms  described in  the
Registration  Statement  (after  it  is  declared  effective),  all  required
corporate action  of the  Company will have  been taken  with respect  to the
issuance and sale  of such Debt  Security, and such  Debt Security will  have
been validly issued and will constitute a valid and binding obligation of the
Company, enforceable in accordance with its terms; and

     (iii) when  a Guarantee  has been  duly  executed and  delivered by  the
Company, all  corporate actions  of the  Company will  have  been taken  with
respect to the issuance of such Guarantee, and such Guarantee will constitute
a valid and binding agreement of the  Company, enforceable in accordance with
its terms.

     The opinions set  forth herein are limited to matters of the laws of the
State of  New York.  With  respect to the laws  of the State of  Delaware, we
have made no  independent investigation of such  laws and have relied  on all
matters governed by  such laws upon the opinion of Richards, Layton & Finger,
P.A.  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 "Validity of Securities" 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

                                   BROWN & WOOD LLP