Community-based participatory research (CBPR) is research that is conducted as an equal partnership between traditionally trained “experts” and members of a community. In CBPR projects, the community participates fully in all aspects of the research process. CBPR projects start with the community. Community is often self-defined, but general categories of community include geographic community, community of individuals with a common problem or issue, or a community of individuals with a common interest or goal. CBPR encourages collaboration of “formally trained research” partners from any area of expertise, provided that the researcher provide expertise that is seen as useful to the investigation by the community, and be fully committed to a partnership of equals and producing outcomes usable to the community. Equitable partnerships require sharing power, resources, credit, results, and knowledge, as well as a reciprocal appreciation of each partner’s knowledge and skills at each stage of the project, including problem definition/issue selection, research design, conducting research, interpreting the results, and determining how the results should be used for action. CBPR differs from traditional research in many ways. One of the principal ways in which it is different is that instead of creating knowledge for the advancement of a field or for knowledge’s sake, CBPR is an iterative process, incorporating research, reflection, and action in a cyclical process.