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                                                           EXHIBITS (5) & (23)



                                                   July 28, 2005



Merrill Lynch & Co., Inc.
4 World Financial Center
New York, New York 10080

Ladies and Gentlemen:

         As your counsel, we have examined a copy of the Restated Certificate
of Incorporation, as amended, of Merrill Lynch & Co., Inc. (hereinafter called
the "Company"), certified by the Secretary of State of the State of Delaware.
We are familiar with the corporate proceedings had in connection with the
proposed issuance and sale by the Company through the Agent referred in and
pursuant to a Distribution Agreement dated December 15, 2004 (the
"Distribution Agreement"), between the Company and Merrill Lynch & Co.,
Merrill Lynch, Pierce, Fenner & Smith Incorporated ("MLPF&S"), of up to
$39,390,000,000 of its Medium-Term Notes, Series C and which are designated as
"Medium-Term Notes, Series C, 2% Notes Linked to the Performance of the Dow
Jones CBOT Treasury Index due July 28, 2008" (the "Notes"). We have also
examined a copy of the Indenture between the Company and JPMorgan Chase Bank,
N.A., as Trustee, dated as of April 1, 1983, as amended (the "Indenture"), and
the Company's





Registration Statement on Form S-3 (File No. 333-122639) relating to the Notes
(the "Registration Statement").

         Based upon the foregoing and upon such further investigation as we
deemed relevant in the premises, we are of the opinion that the Notes have
been duly and validly authorized by the Company and when the Notes have been
duly executed and authenticated in accordance with the terms of the Indenture
and delivered against payment therefor as set forth in the Distribution
Agreement, the Notes will constitute valid and legally binding obligations of
the Company, enforceable against the Company in accordance with their terms,
except to the extent that enforcement thereof may be limited by bankruptcy,
moratorium, insolvency, reorganization or similar laws relating to or
affecting creditors' rights generally and except as enforcement thereof is
subject to general principles at equity (regardless of whether enforcement is
considered in a proceeding in equity or at law).

         We consent to the filing of this opinion as an exhibit to the
Registration Statement and as an exhibit to the Current Report of the Company
on Form 8-K dated July 28, 2005. We also consent to the use of our name under
the caption "United States Federal Income Taxation" in the pricing supplement
and prospectus supplement related to the offering of the Notes.

                                                    Very truly yours,



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