Rem Koolhaas (1944) is a Dutch architect, architectural theorist, urbanist, and Professor in Practice of Architecture and Urban Design at the Graduate School of Design at Harvard University. Koolhaas studied at the Architectural Association School of Architecture in London and at Cornell University in Ithaca, New York. He is the founding partner of OMA, and of its research-oriented counterpart AMO based in Rotterdam, the Netherlands.

He is widely regarded as one of the most important architectural thinkers and urbanists of his generation. In 2000, Rem Koolhaas won the Pritzker Prize. In 2008, Time magazine included him in their top 100 of The World's Most Influential People.