EXHIBIT 24
POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that the undersigned
hereby severally constitutes and appoints John
Kingston, III, Darrell W. Crate and Nathaniel Dalton,
and each of them singly, with full power of
substitution and resubstitution, as the undersigned's
true and lawful attorney-in-fact with full power and
authority to them, and each of them singly, to
prepare, sign and file for the undersigned, in the
undersigned's name and capacity indicated below, any
and all filings and documents (including without
limitation any exhibits and amendments thereto) of the
undersigned or Affiliated Managers Group, Inc.
pursuant to the Securities Exchange Act of 1934, as
amended (the "Act"), including without limitation
filings pursuant to Section 16 of the Act and the
rules and regulations promulgated thereunder, and
generally to do all such things in the undersigned's
name and capacity indicated below to enable the
undersigned and Affiliated Managers Group, Inc. to
comply with the provisions of the Act and all
requirements of the Securities and Exchange
Commission, hereby ratifying and confirming the
undersigned's signatures as they may be signed by said
attorneys, or any of them, or any substitute or
substitutes of any of them, on said filings,
documents, exhibits and any and all amendments
thereto, and hereby ratifying and confirming all that
said attorneys, or any of them, or any substitute or
substitutes of any of them, may lawfully do or cause
to be done by virtue hereof.

Witness my hand, this 22nd day of April, 2008.


By:	/s/ Jay c. Horgen
Name:	Jay C. Horgen
Title:	Executive Vice President