Rem Koolhaas founded OMA in 1975 together with Elia and Zoe Zenghelis and Madelon Vriesendorp. He graduated from the Architectural Association in London and in 1978 published Delirious New York: A Retroactive Manifesto for Manhattan. In 1995, his book S,M,L,XL summarized the work of OMA in "a novel about architecture." He heads the work of both OMA and AMO, the research branch of OMA, operating in areas beyond the realm of architecture such as media, politics, renewable energy and fashion. Koolhaas has won several international awards including the Pritzker Architecture Prize in 2000 and the Golden Lion for Lifetime Achievement at the 2010 Venice Biennale. Koolhaas is a professor at Harvard University where he conducts the Project on the City.

Reinier de Graaf joined OMA in 1996 as project director for De Rotterdam, the Netherlands' largest building, which is currently under construction. In 2002 he became director of AMO, the think tank of OMA, and produced "The Image of Europe," an exhibition illustrating the history of the European Union. He led several OMA projects in the Middle East, and in 2009 led the competition-winning design for Rotterdam's Stadskantoor. De Graaf is also working on the Commonwealth Institute redevelopment in London. He is responsible for AMO's increasing involvement in sustainability and energy planning, which has included the publication in 2010 of "Roadmap 2050: A Practical Guide to a Prosperous, Low-Carbon Europe" with the European Climate Foundation and "The Energy Report," a global plan for 100 percent renewable energy by 2050, made with the WWF.