Prevention and intervention research studies often fail to include an assessment of program integrity, and when they do, it is often examined in a limited way. Further, despite efforts to reform the intervention research process to include community stakeholders more actively in every phase of investigation, current practice generally employs a hierarchical model of integrity that fails to be responsive to community needs and priorities. In this article, we describe the traditional, hierarchical model of integrity and contrast this framework with a partnership model of treatment integrity. The limitations of the hierarchical model are illustrated through the description of two school‐based prevention programs. Core features of the partnership model and steps for implementing this framework in research and practice are described. Although the partnership model has limitations when conducting efficacy research in clinical trials, it has clear advantages over the hierarchical model in conducting effectiveness research and research that is directly linked with practice. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 495–507, 2005.