Under the Western Economic Diversification Act, the Department is mandated to "promote the development and diversification of the economy of Western Canada and to advance the interests of Western Canada in national economic policy, program and project development and implementation".

In order to achieve this mandate, Western Economic Diversification Canada has worked with, and on behalf of, western Canadians to address a wide range of issues that affect the region's long-term prosperity and the ability of its communities to prosper economically.