Claude de Forest was born in 1931 in Basel, Switzerland. Both his uncle and grandfather were architects and as a child he was encouraged to frequent construction sites and even had his own desk in the architecture office. In 1949, the family emigrated to Canada, settling in Montreal where de Forest studied engineering at McGill University (1950-1951) and received his B.A. in architecture from the University of Manitoba in Winnipeg in 1955. He received his M.A. in architecture from MIT in 1956 before being hired by Eero Saarinen as a cartoonist and junior designer for Eero Saarinen & Associates from 1956-1958. Significant projects include Yale University: the Ingalls Hockey Rink, the IBM Research Center, TWA Terminal, University of Pennsylvania dormitory and Chicago Law School.

In 1958, de Forest traveled on a study trip to the Far East and then settled in Switzerland where he worked as a designer in his uncle’s firm. From 1959-1993, de Forest taught architecture at the University of Manitoba in Winnipeg and was a design consultant and partner on a number of architectural and urban planning projects. He became interested in housing and environmental design for individuals with disabilities and from 1991-1993 served as the Executive Director of the Canadian Institute for Barrier-Free Design.

De Forest married Yoshiko Hasegawa in Kyoto, Japan in 1960. He died on December 30, 2013 in Winnipeg, Canada, survived by his wife and three children.