Recent attention to closing the research to practice gap reflects a new paradigm in which community partners assume more active roles in intervention research. Funders are shaping this new genre of collaborative research, and yet still require letters of support from investigators documenting access to sites as evidence of feasibility. Defining feasibility by access, however, derives from a basic research model that translates poorly to a collaborative one. At the same time, university–community collaboration within externally funded research poses a number of ethical challenges. We encourage a redefinition of feasibility that prioritizes collaboration by reconstructing the purpose and content of letters of support and by encouraging investigators to build into studies sufficient time and specific plans for building sustainable partnerships.