[Working across sectors and with citizens to create a healthy living environment: what works, why, and in what context].

Introduction: Promoting a healthy living environment requires cross-sector collaboration between governments, social organizations, and citizens. The factors influencing cross-sectoral collaboration and citizen participation are generally well known. Less well known is how these factors work and in what context, such as priority neighborhoods. This study explores the effective factors for cross-sector collaboration with citizen participation in priority neighborhoods. Methods: We combined participatory action research with realist evaluation in three Dutch neighborhoods, in both rural and urban municipalities named X, Y and Z in the east of the Netherlands. Data collection included document analysis ( Results: Six effective elements for cross-sector collaboration with citizen participation are: 1) room for cross-sectoral collaboration and citizen participation, 2) cross-domain facilitators and key figures from the neighborhood as health brokers, 3) personal contact and presence in the neighborhood, 4) equity and expectation management, 5) open and regular communication, and 6) visible results.We have experienced that the design of the study as a learning process, facilitated by an action researcher and local process guidance, contributes to sustainable relationships, local impact, and joint ownership. Conclusion: To effectively shape cross-sectoral collaboration that involves citizen participation in priority neighborhoods, it is important to create opportunities for learning processes, bridging roles, relationship-building, and local perspectives.