OPINION RE: LEGALITY; CONSENT OF COUNSEL

EXHIBIT (5) & (23)

November 24, 1998

Merrill Lynch & Co., Inc.
World Financial Center
North Tower
New York, New York 10281

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 to the Underwriters named in the Terms
Agreement referred to below, pursuant to an Underwriting Agreement dated August
5, 1998 (the "Underwriting Agreement"), between the Company and Merrill Lynch &
Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated ("MLPF&S"), as
supplemented by a Terms Agreement, dated November 17, 1998 (the "Terms
Agreement") among the Company, MLPF&S and the other underwriters named therein
(the "2004 Underwriters"), relating to $500,000,000 aggregate principal amount
of the Company's 6% Notes due November 15, 2004 (the "Notes due 2004"), and as
further supplemented by a Terms Agreement, dated November 17, 1998 (the

"2018 Terms Agreement", and together with the 2004 Terms Agreement, the "Terms
Agreements") among the Company, MLPF&S and the other underwriters named therein
(the "2018 Underwriters", and together with the 2004 Underwriters, the
"Underwriters") relating to $1,000,000,000 aggregate principal amount of the
Company's 6-7/8% Notes due November 15, 2018 (which, together with the Notes due
2004, are referred to herein as the "Notes"). We have also examined a copy of
the Indenture between the Company and The Chase Manhattan Bank, as Trustee,
dated as of April 1, 1983, as amended and restated (the "Indenture"), and the
Company's Registration Statement on Form S-3 (File No. 333-59997) 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:

1. The Company has been duly incorporated under the laws of the
State of Delaware.

2. 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 Underwriting Agreement, as supplemented by the Terms Agreements, 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, insolvency,
moratorium, reorganization or similar laws relating to or affecting creditors'
rights generally and except as enforcement thereof is subject to general
principles of equity (regardless of whether enforcement is considered in a
proceeding in equity or at law).

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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 November 24, 1998.

Very truly yours,

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