Fasken Martineau DuMoulin LLP (doing business as Fasken) is an international business law firm with approximately 925 lawyers and offices in Vancouver, Surrey, Calgary, Toronto, Ottawa, Montréal, Québec City, London and Johannesburg.

[4] Fasken is the result of a merger between three predecessor firms – Fasken Campbell Godfrey, Martineau Walker, and Russell & DuMoulin.

Fasken Campbell Godfrey in Toronto was formed from the 1989 merger of two long-standing Toronto firms, Fasken & Calvin (which began as Beatty and Chadwick, founded in 1863 by William Henry Beatty and Edward Marion Chadwick)[5] and Campbell Godfrey & Lewtas (which began as Howland & Arnoldi in the 1880s).

In late 1999, Toronto-based Fasken Campbell Godfrey and Quebec-based Martineau Walker (of Montreal and Quebec City) joined together, forming Fasken Martineau.

In February 2000, Vancouver-based Russell & DuMoulin joined the group to create Fasken Martineau DuMoulin LLP.