This article examines community-driven forms of institutionalized collaboration at the regional scale. We advance a generic and scalable framework that captures not only participants and incentives but also the structures and processes that shape urban policy objectives. This framework allows us to track implementation and adaptation, and to assess institutional viability, legitimacy, and performance over time. We find that the Greater Toronto CivicAction Alliance represents a durable and high-performing place-based alliance of social, economic, and political actors dedicated to regional development strategies that include growth and equity goals. Yet the CivicAction Alliance is not a governing coalition. Elite dominance of the policy agenda, value-based tensions, and weak linkages between elected and civic leaders indicate that governance challenges with important democratic implications remain.