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                                                                   Exhibit 10.66

The Goldman Sachs Group, Inc. | 85 Broad Street | New York, New York 10004
Tel: 212-902-5904

Henry M. Paulson, Jr.
Chairman
Chief Executive Officer

                                                                   [LOGO]Goldman
                                                                         Sachs

                                                       February 6, 2001

PERSONAL AND CONFIDENTIAL

Sir John Browne
BP Amoco
Britannic House
1 Finsbury Circus
London, EC2M 7BA
ENGLAND

Dear John:

      In light of the recent Board action modifying aspects of outside director
compensation, we are writing to set forth the current terms of your compensation
as a director of The Goldman Sachs Group, Inc. ("GS Inc."). These terms are, of
course, subject to future modification by the Board.

      As compensation for your services, you will receive:

      o     $35,000 per year (the "Annual Retainer");

      o     $15,000 per year for serving on each of the Board committees of
            which you are a member plus an additional $10,000 per year for
            serving as Chairman of a committee (the "Committee Fees")
            (currently, you are Chairman of the Audit Committee and are a member
            of the Compensation Committee);

      o     $1,000 for each meeting of the Board or of a Board committee that
            you attend (the "Meeting Fees"); and

      o     an annual grant (the "Annual Grant"), at your election on or before
            September 30th of each year, of (a) 2,000 fully vested restricted
            stock units ("RSUs"); (b) fully vested options ("Options") to
            purchase 6,000 shares of GS Inc. common stock; or (c) 1,000 RSUs
            and Options to purchase 3,000 shares of GS Inc. common stock.

      The Annual Retainer and the Committee Fees will be paid annually in
arrears in the form of RSUs unless GS Inc. determines to pay them in cash. On
December 28, 2000, you were
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granted 870 RSUs in respect of the Annual Retainer and the Committee Fees for
the 2000 fiscal year.

      The Meeting Fees are payable in cash and will be paid to you annually in
arrears; your Meeting Fees for the 2000 fiscal year were $12,000 and have been
paid to you.

      RSUs for the Annual Retainer, the Committee Fees and the Annual Grant will
provide for delivery of shares of GS Inc. common stock on the last business day
in May in the year following the date on which you cease to be a director of GS
Inc. All RSUs will be granted to you as of the date of grant of any year-end
equity award granted generally to employees of GS Inc. and its affiliates or, if
no such award is granted, as of the last day of December of such fiscal year (or
in the case of RSUs for the Annual Grant, as of the last day of December of the
fiscal year to which the grant pertains). The number of RSUs you receive for the
Annual Retainer and the Committee Fees will be determined in the same manner as
grants to employees for year-end RSUs granted to employees for that fiscal year
or, if no such RSUs are granted, at a grant price equal to the average closing
price of GS Inc.'s common stock on the New York Stock Exchange over the 10
trading days up to and including the last day of the fiscal year. All RSUs will
be subject to the terms and conditions of the Stock Incentive Plan and the
relevant award agreements.

      For the 2001 fiscal year, you have elected to receive as your Annual Grant
Options to purchase 6,000 shares of GS Inc. common stock; the RSUs issued to you
on December 29, 2000 in respect of that Annual Grant were cancelled and
exchanged for these Options. These Options were granted on January 31, 2001;
will have the same exercise price ($82.875) as options granted to employees for
the 2000 fiscal year; will become exercisable on the earlier of (a) the first
trading day in January 2004 unless that day is not during an "access person
window period" ("Window Period") under GS Inc.'s trading policy, in which case,
the first trading day of the first Window Period that begins thereafter and (b)
the date on which you cease to be a director of GS Inc.; and will expire on
November 26, 2010.

      In the future, any Options granted to you as part of the Annual Grant
will:

            (i)   be granted on the same date as the date of grant of any
                  year-end equity awards granted generally to employees of GS
                  Inc. and its affiliates for the prior fiscal year or, if no
                  such equity awards are granted, on the last day of December in
                  the fiscal year for which the Annual Grant is made;

            (ii)  first become exercisable on the earlier of (a) the same date
                  that year-end options granted generally to employees of GS
                  Inc. and its affiliates for the prior fiscal year become
                  exercisable or, if no such options are granted, on the first
                  trading day in January three years after the date of grant
                  unless that date is not during a Window Period, in which case
                  the first trading day of the first Window Period that begins
                  thereafter and (b) the date on which you cease to be a
                  director of GS Inc;

            (iii) have an exercise price equal to the exercise price of any
                  year-end options granted generally to employees of GS Inc and
                  its affiliates for the prior fiscal year or, if no such
                  options are granted, the closing price of GS Inc.'s
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            (iv)  will expire ten years after the date of grant.

      We have enclosed various documents in connection with awards previously
made to you. Please sign where indicated and return them to Bob Katz in the
enclosed envelope. The remaining copies are for your records.

                                     Very truly yours,

                                     THE GOLDMAN SACHS GROUP, INC.


                                     By /s/ Henry M. Paulson, Jr.
                                        ----------------------------
                                        Henry M. Paulson, Jr.
                                        Chairman and Chief Executive
                                        Officer

Enclosures: RSU Award Agreement for Fiscal Year 2000 Annual Retainer
              and Committee Fees and Award Summary
            RSU Award Agreement for Fiscal Year 2000 Annual Grant
              and Award Summary
            Option Award Agreement for Fiscal Year 2001 Annual Grant
              and Award Summary
            Summary of the Stock Incentive Plan