Purpose. Given the need for comprehensive and multidisciplinary active living interventions, this article describes an innovative partnership for park design and evaluation. Design. The Trust for Public Land partnered with the RAND Corporation and the San Francisco Department of Public Health to generate context-sensitive active park design, establish evaluation methods, and build the framework for future collaboration. Setting. These partners worked together from 2009 to 2012 to design, renovate, and study parks in San Francisco, California. Subjects. The three partnering organizations are the focus of this article. Intervention. The Trust for Public Land's Parks for People-Bay Area Program raised more than $16 million to renovate three San Francisco parks, which served as the intervention for a study that initially brought the three partnering organizations together. Measures. The authors, who represent the three partners, collaborated to develop the lessons learned. Analysis. This article is a description and commentary about a partnership that emphasized community involvement and rigorous evaluation. Results. Lessons learned and elements for successful partnerships include collaborating with organizations with differing expertise, deciding upon goals initially, finding a common language, involving local communities, and recognizing the importance and appropriate role of evaluations. Conclusion. The model for collaboration and community involvement presented supports and encourages other organizations to use strategic, multidisciplinary partnerships and highlights the importance of evaluation.