The Chelsea Barracks site has been dogged with controversy after Prince Charles' criticism of a design by Lord Rogers led to the scheme being axed.
The new team — including landscape architect Kim Wilkie — will draw up a general masterplan, in close consultation with local residents, within which other architects will design the individual buildings.
The Qatari Diar Development Company is leading on the project.
The Rogers scheme was withdrawn by the Qataris in June, a week before it was to be considered by Westminster Council's planning committee. This triggered a £100m lawsuit by the Candys against the Qataris, which began in the High Court last week.
Planning permission for the site may not be given until the end of next year, at the earliest.
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