VANGUARD WINDSOR II FUND
                     INVESTMENT ADVISORY AGREEMENT ADDENDUM

                              EFFECTIVE MAY 1, 2006

This  Addendum  amends  Section  13.1 of Schedule A of the  Investment  Advisory
Agreement  dated December 1, 2003 between  Vanguard  Windsor Funds (the "Trust")
and Hotchkis and Wiley Capital Management, LLC ("H&W," or the "Advisor") for the
management of a portion of Vanguard  Windsor II Fund (the  "Fund"),  a series of
the Trust, as follows:

A. AMENDMENT

1.1.  CALCULATION  OF THE BASE FEE. The Base Fee for each fiscal  quarter of the
Fund is calculated by multiplying an Annual Percentage Rate (shown below) to the
average daily net assets of the H&W Portfolio  during such fiscal  quarter,  and
dividing  the result by four.  The  Fund's  fiscal  quarter  ends are the months
ending January, April, July, and October.

                        Annual Percentage Rate Schedule
                        -------------------------------
                Average Net Assets     Annual Percentage Rate
                ------------------     ----------------------






In the event of termination of this Agreement,  the fee provided in this Section
for the period beginning on the first day of the then-current fiscal quarter and
ending on the last business day on which this Agreement is in effect (the "Short
Quarter") shall be calculated by applying the foregoing annual  percentage rates
to the average daily net assets of the H&W Portfolio  during the Short  Quarter,
dividing the result by four, and multiplying that figure by a ratio equal to the
number of days in the Short  Quarter  divided by the total number of days in the
full quarter.

B. MISCELLANEOUS

Except as specifically  amended  hereby,  all of the terms and conditions of the
Investment  Advisory  Agreement are  unaffected and shall continue to be in full
force and effect and shall be binding  upon the parties in  accordance  with its
terms.

HOTCHKIS AND WILEY CAPITAL                              VANGUARD WINDSOR FUNDS
MANAGEMENT, LLC


/S/ Nancy D. Celick             6/8/06       /S/ John J. Brennan     6/7/06
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Signature                       Date         Signature               Date

NANCY D. CELICK                              JOHN J. BRENNAN
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