This article focuses attention on the institutional context of cross-sector collaboration and its effects on partnership management. Drawing on fieldwork and 54 interviews from 2011 to 2013, we investigate an innovative public–nonprofit partnership within a local unit of the National Park Service. The collaboration demonstrates the power and potential of public–nonprofit partnerships while revealing tensions that cross-sector activities can provoke in an organizational field. We focus on two ongoing processes of institutional change in the nonprofit sector that shape these dynamics: (a) managerialism and (b) empowered agency. We illustrate these processes and suggest that they alter the context for partnerships in national parks, particularly with respect to capacity and control. We conclude by offering several propositions about institutional change and the broader implications of a shifting context for public–nonprofit partnerships.