Grimshaw has pipped Zaha Hadid into second place and snatched victory in the high-profile competition to design the new £140 million Miami Science Museum in the USA.
The practice saw off entries from 35 other international firms, including fellow Brits Wilkinson Eyre, to land the much-sought-after project.
An eight-strong panel of judges picked the London-based architect to design the new museum complex - which will feature an aquarium, a 300-seat planetarium, galleries, laboratories, a rooftop observatory and a studio theatre - after two days of intense judging.
scheme for the 1.6ha site in Museum Park will sit next to Herzog & de Meuron's Miami Art Museum and will replace the institution's existing, 40-year-old museum and planetarium.
Museum benefactors now need to find almost a third of the project's budget before it can get off the ground.
It is hoped the scheme will complete in 2011.by Richard Waite