This book explains why Canadians must rid themselves of interprovincial trade barriers. Canada's provinces do almost as much trade with each other as they do with the rest of the world. But trade between the provinces is harder than with foreign countries. We trouble our own house with an amazing variety of barriers: professionals and tradespeople cannot move freely and practice where they wish, regulation makes it hard for investments to flow to where they are most needed, provincial governments give contracts to local firms even though out-of-province firms can do the job at a lower cost, Ottawa pays the most generous UI to regions with the highest unemployment and thereby encourages people to stay in parts of the country with little promise. The effects of such barriers on the economy are difficult to measure, which may be the reason that little has been done about them. But Canadians cannot afford to ignore their costs. The European Community is very close to the goal of ensuring free trade among its members. Unless we unlock our potential we may fall behind other countries and communities that have recognized the importance of internal as well as external free trade.