June 25, 2008 - U.S. architectural firms pulled in a combined $1.74 billion from green design projects in 2007 - $1.62 billion in the U.S. and $121.2 million abroad, according to Engineering News-Record (ENR).

The magazine's first-ever "Top Green Design Firms" survey ranks the top 100 firms based on 2007 design revenue from projects that have been recognized by independent certification standards such as the U.S. Green Building Council's LEED program.

St. Louis-based architectural firm HOK topped the list, raking in more money from green-certified building projects last year than any other U.S. shop. Recent projects in the firm's design portfolio include the first building in Latin America to achieve LEED Gold status and first major U.S. sports arena to achieve LEED certification.

View ENR's list of the top 100 green-design firms here.