Community-based research challenges the traditional research paradigm by recognizing that complex social problems in the early 21st century must involve multiple stakeholders in the research process—not as subjects but as coinvestigators and coauthors. It is an orientation to inquiry rather than a methodology and reflects a transdisciplinary paradigm by including academics from many disciplines, community members, activists, and often students in all stages of the research process. Community-based research is relational research where all participants change and grow in a synergistic relationship as they work together and strategize to solve issues and problems that are defined by and meaningful to the community. This chapter is an introduction to the historical and philosophical roots of community-based research and discusses the core principles and skills useful when designing and working with community members in a collaborative, innovative, and transformative research partnership. The rationale for working within this research paradigm is discussed, as well as the challenges researchers and practitioners face when conducting community-based research. This chapter ends with a discussion of the continuing need for discussion, reflection, and case studies from the field regarding professional boundaries, institutional barriers, ethical research practices, and project evaluation.