This chapter explores the historical development of the retail sector in the United States and Canada, connecting the evolution of retail formats with changes in the economy, technology, shopping practices and consumer attitudes. Retailing is considered as both a competitive profit-seeking enterprise and as a set of social and cultural practices. The analysis stretches from trading post to e-commerce, beginning with a reappraisal of pre-industrial retailing that rejects underdevelopment and subsistence arguments. As the processes of making, distributing and selling became systematised and standardised, retailing expands dramatically, changing what people buy, as well as where and how they shop. The chapter ends with a discussion of current transformations in technology and shopping patterns that are challenging long-held models of mass retailing and forcing change. Comparisons of retailing environments and strategies in America and Canada are used to illustrate the impact of geography, demographics, regulation and cultural difference. Retailing in Canada and the United States is shown to be complex, heterogeneous, ever present and continuously evolving. Entirely new retail formats and strategies emerge, existing ones are reconfigured and small enterprises persist amidst changing conditions and opportunities.