WilmerHale

Jason L. Kropp

+1 617 526 6421 (t)
+1 617 526 5000 (f)
jason.kropp@wilmerhale.com

May 14, 2010

BY ELECTRONIC SUBMISSION

U.S. Securities and Exchange Commission
Division of Corporate Finance
100 F Street, N.E.
Washington, DC 20549

Attn: Hagen Ganem

Re: Ameresco, Inc.
Registration Statement on Form S-1
Filed March 31, 2010
File No. 333-165821

Ladies and Gentlemen:

Submitted herewith for filing on behalf of Ameresco, Inc. (the “Company”) is Amendment No. 2 (“Amendment No. 2”) to the Registration Statement referenced above (the “Registration Statement”). The Company is filing Amendment No. 2 solely for the purpose of filing Exhibits 10.5 and 10.16 to the Registration Statement.

Please contact the undersigned (617-526-6421) or Patrick Rondeau (617-526-6670) with any questions or comments you may have regarding this filing.

Very truly yours,

/s/ Jason L. Kropp

Jason L. Kropp

Wilmer Cutler Pickering Hale and Dorr llp, 60 State Street, Boston, Massachusetts 02109

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