To address the negative environmental, political, and social consequences of the dominant, industrialized global food system, communities around the world have developed goals and values underlying a sustainable food system. Conceptualizing food production, distribution, and consumption as systems helps clarify the ways food affects social and natural environments, with the distribution element as the critical juncture where the product reaches the consumer. Urban food systems are a particularly important environment in which to study movements toward sustainability. This paper focuses on the movement for a sustainable food system in Portland, Oregon, with particular focus on the city’s markets for food acquisition – food retail, farmers’ markets, community supported agriculture endeavors, restaurants, food service and distribution companies, institutional purchasing programs, and community gardens, as well as the organizations that support the work of these businesses and programs. Leaders in the field of sustainable food systems are now beginning to operate with a strategy for change that emphasizes incorporating sustainable food products and sustainable food system values into mainstream food markets instead of remaining in niche, alternative markets as has occurred in the past. This notion is supported by economic and social theories including the consumer information model, stakeholder theory, social movement theories of change, and network theories. This paper explores the extent to which Portland food distribution businesses, programs, and organizations attempt to fulfill the goals of a sustainable food system movement with moving from niche to mainstream in mind. The fact that the movement is in fact acting according to new strategies for change emphasizing the mainstream is indicated by the movement’s extensive consumer education and creative use of marketing, strong social and business networks, and organized local policy influences.