SECURITIES AND EXCHANGE COMMISSION


                             Washington, D.C. 20549


                                    FORM 8-K


                                 CURRENT REPORT

                       Pursuant to Section 13 or 15(d) of
                      the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  December 22, 1999
                                                   -----------------

                           Merrill Lynch & Co., Inc.
                           -------------------------
             (Exact name of Registrant as specified in its charter)


         Delaware                 1-7182                        13-2740599
- --------------------------------------------------------------------------------
      (State or other           (Commission                   (I.R.S. Employer
      jurisdiction of           File Number)                 Identification No.)
      incorporation)



World Financial Center, North Tower, New York, New York   10281-1332
- --------------------------------------------------------------------

      (Address of principal executive offices)            (Zip Code)


Registrant's telephone number, including area code: (212) 449-1000
                                                    --------------



         (Former name or former address, if changed since last report.)

Item 5.  Other Events
- -------  -------------

     Exhibits are filed herewith in connection with the Registration Statements
on Form S-3 (File Nos. 333-59997 and 333-68747) filed by Merrill Lynch & Co.,
Inc. (the "Company") with the Securities and Exchange Commission covering Senior
Debt Securities issuable under an indenture dated as of April 1, 1983, as
amended through the date hereof, between the Company and The Chase Manhattan
Bank (as so amended, the "Indenture"). The Company will issue $47,000,000
aggregate principal amount of Global Market Index Target-Term Securities(R) due
December 22, 2004 under the Indenture.  The exhibits consist of the form of
Securities and an opinion of counsel relating thereto.

Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits
         ------------------------------------------------------------------

                         EXHIBITS

          (4)            Instruments defining the rights of security holders,
                         including indentures.

                         Form of Merrill Lynch & Co., Inc.'s Global Market Index
                         Target-Term Securities due December 22, 2004.

          (5) & (23)     Opinion re: legality; consent of counsel.

                         Opinion of Brown & Wood LLP relating to the Global
                         Market Index Target-Term Securities due December 22,
                         2004 (including consent for inclusion of such opinion
                         in this report and in Merrill Lynch & Co., Inc.'s
                         Registration Statements relating to such Securities).

                                       2

                                   SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
 registrant has duly caused this report to be signed on its behalf by the
 undersigned, thereto duly authorized.

                              MERRILL LYNCH & CO., INC.
                              -------------------------
                                     (Registrant)


                              By:  /s/     John C. Stomber
                                   -----------------------------
                                        John C. Stomber
                                     Senior Vice President
                                              and
                                           Treasurer

Date:  December 22, 1999

                                       3

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549




                           MERRILL LYNCH & CO., INC.




                         EXHIBITS TO CURRENT REPORT ON
                        FORM 8-K DATED DECEMBER 22, 1999



                                              Commission File Number 1-7182

                                 Exhibit Index

Exhibit No.   Description                                                   Page
- -----------   -----------                                                   ----

(4)           Instruments defining the rights of security holders,
              including indentures.

                    Form of Merrill Lynch & Co., Inc.'s Global Market Index
                    Target-Term Securities due December 22, 2004.

(5) & (23)    Opinion re:  legality; consent of counsel.

                    Opinion of Brown & Wood LLP relating to the Global Market
                    Index Target-Term Securities due December 22, 2004
                    (including consent for inclusion of such opinion in this
                    report and in Merrill Lynch & Co., Inc.'s Registration
                    Statements relating to such Securities).