The World's Largest Architecture Firms

Vanessa Quirk discusses the results of Building Design's annual listing of the largest architecture firms in the world. The architecture and engineering behemoth Aecom has claimed top spot (up from number 2 last year) with 1,370 employees.

1 minute read

February 13, 2013, 5:00 AM PST

By Jonathan Nettler @nettsj


"Building Design has released their annual ranking, The WA100, of the world’s largest architecture firms. Coming in the #1 spot (up from #2 last year) is Aecom, who, with 1,370 employees worldwide, narrowly outranked Gensler (with 1,346 employees). Completing the top three was IBI Group (1,129 employees). Aecom, Gensler, and Japanese-based firm Nikken Sekkei (ranked #4) were the top 3 earners of 2012, each making over $400 million US Dollars in Fee Income."

"Interestingly," notes Quirk, "the only firms to grace both the Top 10 list and Building Design’s survey of the Top 5 Most Admired Firms of 2012, were Gensler (#2 Largest; #4 Most Admired) and Foster & Partners (#10 Largest; #1 Most Admired). Zaha Hadid Architects (who shared the number 5 Most Admired spot with Rogers Stirk Harbour & Partners, ranked as the 45th largest firm)."

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