The global real estate investment manager's economic growth index is based on factors such as employment and population growth, as well as momentum and risk factors including volatility, diversity and business costs. All told, 36 North American cities were evaluated and four Canada cities are in the top 15, with Vancouver, coming in at No. 13 and Montreal No. 15.

Underpinning Toronto's strength is its diverse economy, according to the report. "Although the city's manufacturing sector and the closely tied transportation sector have undergone some recent weakness as the Canadian dollar and oil prices have increased, both sectors are anticipated to improve in the coming years," states LaSalle. Strong employment and population growth through 2009, as well as a positive economic outlook, were other major factors behind Toronto's top ranking, according to the report.

The office center for Alberta's energy industry, Calgary, has been boosted by strong oil and gas demand, which have contributed to the city's low-tax environment, according to the report. That, in turn, has attracted more energy companies. Imperial Oil recently relocated its headquarters there after 124 years in Toronto, according to the report.