February 26, 2008

U.S. Securities & Exchange Commission
Attn: Filing Desk
100 F Street, N.E.
Washington, DC 20549
Attn: Filing Desk

RE: Vanguard Explorer Fund (the "Trust")
        2-27203

Ladies and Gentlemen:

Enclosed  is the  81st  Post-Effective  Amendment  to the  Trust's  registration
statement  on Form N-1A,  which we are filing  pursuant to Rule 485(a) under the
Securities  Act of 1933.  The purposes of this amendment are (1) to disclose the
removal of Grantham,  Mayo, Van Otterloo & Co., LLC as an investment  adviser of
Vanguard  Explorer  Fund and (2) to  effect a number of  non-material  editorial
changes.

Pursuant to the  requirements  of Rule 485(a)(2) we have designated an effective
date of April 29, 2008 for this amendment. Prior to the effective date, Vanguard
will  submit a Rule 485(b)  filing that will  include  text  addressing  any SEC
comments,  as  well  as  updated  financials  for  the  Fund.  Pursuant  to Rule
485(d)(2),  the 485(b)  filing will  designate  the same  effective  date as the
485(a) filing.

If you have any questions or comments concerning the enclosed Amendment,  please
contact me at (610) 503-2398.


Sincerely,



Barry A. Mendelson
Principal
The Vanguard Group, Inc.

Enclosures

cc: Christian Sandoe, Esq.
U.S. Securities and Exchange Commission