This article explores the contributions to Canadian policy development and policy thought of three royal commissions of political-economic inquiry: the 1940 Royal Commission on Dominion-Provincial Relations; the 1958 Royal Commission on Canada's Economic Prospects; and the 1985 Royal Commission on the Economic Union and Development Prospects for Canada. Each commission is examined through tree areas of concern: The context for its appointment, the content of its report and the nature of its subsequent influence.