Canadian political parties are charged with aggregating the interests of a diverse and changing electorate in order to balance particularistic local demands with general national interests. This article asks what kind of organizations have they adopted to do this? How does their organizational character shape their capacities and their practices? The argument outlines a franchise organization model and explores the extent to which it can be used to explain Canadian party behaviour. The article exploits this model to analyze questions of party membership, the place of incumbents, leadership and electoral organization as they are played out in Canadian politics.