Behaviors associated with cancer screening have been the focus of intensive research over the past 2 decades, primarily in the form of intervention trials to improve screening based in both clinical and community settings. Meta-analyses and literature reviews have synthesized and organized the resulting literature. From the accumulated work, this review distilled lessons learned from cancer screening intervention research in community settings. The authors posed the question, “What do we know about the development of effective community-based interventions (the level of good over harm achieved in real-world conditions)?” Framed around the concept of focal points (the simultaneous combination of target population, behavioral objective, and setting for an intervention), 13 lessons were derived. One lesson was cross-cutting, and the other lessons addressed the three focal-point components and the major intervention categories (access-enhancing strategies, mass media, small media, one-on-one and small-group education, and combinations of these categories). To build more systematically on existing research, recommendations are made for new directions in basic behavioral and intervention research. Cancer 2004. © 2004 American Cancer Society.