Pressures are increasing on educational policy and practice to use research to guide improvement. Recently there have been concerted efforts to forge new and different kinds of relationships between researchers and practitioners. School districts across the country are developing a new kind of partnership with researchers. These research-practice partnerships are long-term collaborations, which are organized to investigate problems of practice and generate solutions for improving district outcomes. This white paper will: (1) Define research-practice partnerships; (2) Identify the major types of partnerships that operate at the district level; and (3) Describe challenges partnerships face and strategies for addressing these challenges. To do so, the authors draw on a review of existing research and interviews with participants in research-practice partnerships across the country. Throughout, they illustrate the work of research-practice partnerships with portraits of partnerships in action.