Fox was an instrumental force in a partnership that started back in 1976 and quickly rose to prominence, becoming an internationally renowned practice with offices in London, New York and Shanghai.
The company, which was responsible for the World Bank headquarters in Washington, is currently setting out to transform London's skyline with the DIFA building - nicknamed the helter-skelter - in the City.
Fox was the operations manager of the trio, overseeing the general running of the practice and managing the various projects, while William Pedersen was the chief designer and Eugene Kohn the chief marketer.
Born in the Bronx, New York, in 1930, Fox received a bachelor's degree in architecture from the University of Pennsylvania in 1953.
He was a veteran of the US Army, serving as a first lieutenant in the Korean War.
In 1972 Fox, Pedersen and Kohn worked together at John Carl Warnecke & Associates, and four years later decided to set up their own company.
Fox retired 10 years ago, and died on Saturday 16 December at his Connecticut home. He is survived by his wife Judith, and three children.