Populous are an award winning architecture firm, who are famous for all kinds of buildings, but mostly stadiums and racecourses. As I'm sure you all saw, the 2012 London Olympics centred around the huge Olympic stadium, built especially for the event.
Populous were formerly known as HOK Sport Venus Event, founded by Jerry Sincoff in 1983. In January 2009 however, they were bought out and have since operated as an independent architectural firm and large scale event planning organisation. They currently have 12 offices located in all corners of the globe, their headquarters been located in Kansas City, Missouri, USA
As you can it is an amazing stadium and some of their concept stadiums are truly amazing. Such as the proposed 2014 Asian Games Stadium...
Or 'Soccer City', Africa