Abstract Purpose: To explore key contextual factors influencing the viable implementation of a community health promotion program. Better understanding of how contextual factors in local communities can affect the ability of creating community change is useful for practitioners and researchers working in this field. Methods: A formative evaluation of the implementation of a community program to promote child health in four local communities of a large Danish municipality was conducted. This approach facilitated detailed exploration of how contextual factors—such as community readiness, resource availability, and stakeholder engagement—shape implementation success. Data were collected via 15 semi-structured interviews with professional stakeholders and volunteers across the four local communities. Interviews were audio-recorded, transcribed verbatim, and analyzed using an abductive approach to thematic analysis. Results: The analysis, guided by the ‘program life cycle’ framework, identified three central themes across the program development and implementation phases: Program Planning Elements, Professional Networks Supporting Collective Action, and Adaptations Promoting Ownership. Key contextual factors included the recruitment of both mandated and enthusiastic implementation agents, fostering collaborative networks, and allowing for local program adjustments. These factors collectively enhanced ownership, engagement, and alignment with community needs while maintaining the integrity of core program components. Conclusion: Contextual factors play a pivotal role in promoting the successful implementation of community health promotion programs. Effective strategies include assembling diverse teams of implementation agents, enabling local adaptations, and actively engaging stakeholders throughout all phases of program development and implementation. These findings offer actionable insights for effective implementation of contextually responsive health promotion initiatives.