Purpose. To describe the evaluation findings and lessons learned from the Kaiser Permanente Healthy Eating Active Living–Community Health Initiative. Design. Mixed methods design: qualitative case studies combined with pre/post population-level food and physical activity measures, using matched comparison schools for youth surveys. Setting. Three low-income communities in Northern California (combined population 129,260). Subjects. All residents of the three communities. Intervention. Five-year grants of $1.5 million awarded to each community to support the implementation of community- and organizational-level policy and environmental changes. Sectors targeted included schools, health care settings, worksites, and neighborhoods. Measures. Reach (percentage exposed) and strength (effect size) of the interventions combined with population-level measures of physical activity (e.g., minutes of physical activity) and nutrition (e.g., fruit and vegetable servings). Analysis. Pre/post analysis of population level measures, comparing changes in intervention to comparison for youth survey measures. Results. The population-level results were inconclusive overall, but showed positive and significant findings for four out of nine comparisons where “high-dose” (i.e., greater than 20% of the population reached and high strength) strategies were implemented, primarily physical activity interventions targeting school-age youth. Conclusion. The positive and significant changes for the high-dose strategies suggest that if environmental interventions are of sufficient reach and strength they may be able to favorably impact obesity-related behaviors.