National Heritage Areas (NHAs) represent a recent model for protected areas in the U.S. NHAs operate through partnerships with local communities, government agencies, and other organizations. Since 1984, 37 NHAs have been established by Congress, making this one of the fastest growing programs affiliated with the National Park Service and raising important national policy questions. Qualitative research conducted at three NHAs identified several common themes despite wide variations in their geographic, social, economic, and political contexts. This paper reflects on a project that engaged practitioners and other stakeholders in building a collective understanding of NHAs. The group developed a common program theory model, which represents the cyclic and long-term nature of heritage stewardship and is designed to serve as the foundation for an evaluation strategy applicable to all NHAs. The presentation will consider the approaches used, the challenges encountered, and the high stakes policy and management issues entailed.