Robert Sims initially worked for Kuwabara Payne McKenna Blumberg Architects as a student intern while studying architecture at the University of Waterloo. He joined the practice on a full time basis in 1990 and was named an associate in 1995.

Robert has been involved in design development, contract document production and contract administration for a number of the firm's award-winning projects involving components of the conservation of historical buildings. Such projects have included Woodsworth College at the University of Toronto, the Hasbro Toy Headquarters in Pawtucket, Rhode Island and the 237-seat Ettore Mazzoleni Concert Hall renovation at The Royal Conservatory of Music. Robert also served as associate-in-charge of the new Japanese Canadian Cultural Centre, a contemporary institution that honours and serves the cultural needs of the Japanese-Canadian community. This renovated facility is housed within the shell of an existing masonry warehouse in Don Mills, Ontario.

Robert was recently the associate-in-charge of the Master Plan Study and the new Middle School for St. Andrew’s College, a private school facility in Aurora Ontario. He is currently associate-in-aharge of the Royal Conservatory of Music’s new TELUS Centre for Performance and Learning in Toronto.