By the late 1950s, Dickinson was eager to go out on his own. In January 1958 he left Page and Steele, forming Peter Dickinson Associates. The associates were Colin Vaughan, Dick Williams, Rod Robbie, and Fred Ashworth and the firm operated out of the Canadian Petrofina Building at 1910 Yonge Street. The first project the new firm received was the Seminary for the Jesuit Fathers of Upper Canada, located in North York. Significant projects from the early days of the new firm included the 55 Yonge Street office building, the Continental Can Building, and the 500 Avenue Road apartments. The new firm had also opened offices in Ottawa and Montreal, designing an array of buildings in both of those cities.