Born in Toronto, Johnson earned his B.F.A. in landscape architecture in 1958 from the University of Illinois, where he was the Edward Ryerson Fellow. He then worked for the Toronto-based firm Project Planning Associates, Ltd. (PPAL) on such projects as the St. Lawrence Parks system and the Kuwait waterfront. In 1963, he received his M.L.A. and the Charles Eliot Traveling Fellowship from Harvard’s Graduate School of Design, before returning to PPAL and helping to plan the International and Universal Exposition of 1967, in Montreal.
In 1966, Johnson partnered in the firm Johnson Sustronk Weinstein + Associates, and was the principal designer of the master plan for the Metropolitan Toronto Zoo. His other projects include Centreville Village on Centre Island; Humber Bay Park; Colonel Samuel Smith Park; and the IBM Headquarters in Markham. After leaving the firm in 1982, Johnson founded Brad Johnson + Associates, Ltd., a private consultancy whose credits include the redesign of Philosopher’s Walk, at the University of Toronto, and (with Phillip Weinstein) the master plan for the expansion of Durham College, in Oshawa, Ontario. Johnson has been a visiting critic at the University of Guelph, the University of Toronto, and the University of Canberra (Australia), among others. A recipient of many professional awards and honors, he is a Fellow (1974) and past president (1988) of the Canadian Society of Landscape Architects, and in 1975, he was elected an Academician of the Royal Canadian Academy of Art.