VANGUARD WINDSOR II FUND
                     INVESTMENT ADVISORY AGREEMENT ADDENDUM

                              EFFECTIVE MAY 1, 2006

This Addendum amends the first paragraph of section 4 of the Investment Advisory
Agreement  dated November 1, 1991 between  Vanguard  Windsor Funds (the "Trust")
and  Tukman  Capital  Management,  Inc.  ("Tukman,"  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

4.  COMPENSATION  OF  ADVISOR.  For the  services  to be  rendered  by Tukman as
provided  in this  Agreement,  Windsor  II shall pay to Tukman at the end of the
Fund's fiscal  quarters,  a basic fee  calculated by applying a quarterly  rate,
based on the following annual  percentage rates, to the average daily net assets
of the Tukman Portfolio for the quarter:


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  Tukman  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.

TUKMAN CAPITAL MANAGEMENT, INC.           VANGUARD WINDSOR FUNDS


Daniel Grossman                 6/9/06    John J. Brennan       6/5/06
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Signature                       Date      Signature             Date


DANIEL GROSSMAN                           JOHN J. BRENNAN
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