From early educational and residential projects, the firm rose to prominence in the early 1950s, winning Governor General's Medals in Architecture and commissions from the government of Ontario for departmental buildings, and it went on to design prominent landmarks such as Purdy's Wharf in Halifax, Nova Scotia, and the redesign of Nathan Phillips Square in Toronto.

After the completion of some small-scale residential and commercial projects, the two partners received their first large commission in 1947 from the Ontario Food Terminal Board in Toronto.

The latter building won Shore and Moffat another Massey Medal and launched the firm into the research field, bringing them projects for Petro Canada, Royal Dutch Shell and Teck Cominco.

The builders chose to give the building an interesting mix of materials; granite, nickel and stainless steel creating a countenance full of dignity and character.

Even though STIP continued to win awards, the firm was seen as coasting on its reputation, failing to provide forward-looking design and planning, and faced the danger of becoming simply a drawing production office.

Under Frontini's direction, the Whitby Public Library and Civic Square was completed and featured in, and on, the cover of Canadian Architect magazine.

Duff Balmer, the designer of the Angus Glen Community Centre in Markham, Ontario, was also an integral part of the renaissance at STIP.

Balmer is credited as the lead designer on the Health and Wellness Centre at the UofT Mississauga Campus; the former winning the National Post/Design Exchange Silver Award in 2005.

Environmental sustainability has become more and more prevalent in STIP's designs, demonstrated in the greenhouse gas reduction technology used in the Fathom Five National Marine Park/Bruce Peninsula National Park visitors' centre, The Wellness Centre at the UofT Mississauga Campus (UTM) also incorporated green roofs, one of which was intended for use by the biology department.

On March 8, 2007, it was announced at Toronto City Hall that STIP, along with PLANT Architect, had been awarded the $40 million redesign of the iconic Nathan Phillips Square.

In May 2011, the firm merged with Ottawa-based Vermeulen Hind Architects and, together with Vancouver-based Busby Perkins+Will, the three rebranded to form Perkins+Will Canada, a unified national practice.