[1] The company was relatively small until Bernard Lamarre joined Lavalin in 1952, after marrying Louise Lalonde, Jean-Paul's daughter.
By the mid-1980s, Lavalin was the largest engineering firm in Canada with 5,700 employees, surpassing their rivals SNC, with revenues of C$500 million in 1983.
[2][3] In the mid 1980s, the company was retained for the design-build contract to complete the Montreal's Olympic Stadium including the 20,000 square meter retractable fabric roof.
They then purchased a number of companies unrelated to their engineering core, including the Kemtec petrochemical plant, the Bellechasse Hospital in Montreal, MétéoMédia's Weather Channel properties, book publisher Mondia, and attempted to enter the aircraft leasing business.
In 1991, Lavalin's bankers put it under pressure to be acquired by its chief rival, SNC, a deal that was concluded in August for C$400 million.