Below are the 50 firms that did the best in our rankings according to their commitment to sustainability practices and the green certifications of their projects.

2012 Architect 50: Sustainability Rankings
Rank Firm Name
1 Westlake Reed Leskosky Cleveland
2 EHDD San Francisco
3 Pearce Brinkley Cease + Lee Raleigh, N.C.
4 William Rawn Associates Boston
5 RNL Denver
6 Payette Boston
7 Frank Harmon Architect Raleigh, N.C.
8 BNIM Kansas City
9 The Miller Hull Partnership Seattle
10 Zimmer Gunsul Frasca Architects (ZGF) Portland, Ore.
11 DLR Group Omaha, Neb.
12 Lord Aeck & Sargent Atlanta
13 Pei Cobb Freed & Partners Architects New York
14 Tate Snyder Kimsey Las Vegas
15 SmithGroupJJR Detroit
16 Architectural Resources Cambridge (ARC) Cambridge, Mass.
17 Little Diversified Architectural Consulting Charlotte, N.C.
18 John Ronan Architects Chicago
19 Richärd+Bauer Phoenix
20 EYP Architecture & Engineering Albany, N.Y.
21 LMN Architects Seattle
22 Kaplan McLaughlin Diaz Architects (KMD) San Francisco
23 Ehrlich Architects Culver City, Calif.
24 Leddy Maytum Stacy Architects San Francisco
25 HOK St. Louis
26 HGA Architects and Engineers Minneapolis
27 Ross Barney Architects Chicago
28 Adrian Smith + Gordon Gill Architecture Chicago
29 BKSK Architects New York
30 Cannon Design Grand Island, N.Y.
31 Perkins+Will Chicago
32 Integrated Architecture Grand Rapids, Mich.
33 Schrader Group Architecture Phildelphia
34 H3 Hardy Collaboration Architecture New York
35 LPA Irvine, Calif.
36 Clark Nexsen Norfolk, Va. 
37 Ratcliff Architects Emeryville, Calif.
38 NAC | Architecture Seattle, Wash.
39 Helix Architecture + Design Kansas City
40 Studios Architecture Washington, D.C.
41 FxFowle New York
42 Eskew+Dumez+Ripple New Orleans
43 Centerbrook Architects and Planners Centerbrook, Conn.
44 RDG Planning & Design Ames, Iowa
45 Fanning Howey Celina, Ohio
46 HDR Architecture Omaha, Neb.
47 Tsoi/Kobus & Associates Cambridge, Mass.
48 HMC Architects Los Angeles
49 Mark Cavagnero Associates Architects San Francisco
50 Ayers Saint Gross Baltimore, Md. 

To read the rest of our 2012 ARCHITECT 50 coverage, click here.