Background <p>Mental health promotion has become an increasing priority in Norwegian public health work, particularly in response to rising mental health challenges. The Act-Belong-Commit (ABC) framework was piloted in three municipalities in Trøndelag county, Central Norway, before being adopted as a national campaign in 2025. Despite its rapid rollout, little is known about how such public mental health campaigns can be implemented and their potential for creating health-promoting settings. In this article we therefore identify the inhibiting and promoting factors in the implementation of ABC and ask if ABC can create more mental health promoting settings.</p> Method <p>This qualitative implementation study draws on semi-structured interviews conducted between May and October 2025 with 16 informants across four municipalities (two pilot, two non-pilot) in Trøndelag county, Norway. Data were analysed using thematic analysis, identifying five themes: background and timing, organisational structure, actions and activities, communication and collaboration, and material and evaluation.</p> Results <p>Promoting factors included timely uptake, leadership support, cross-sectoral public health teams, and integration into existing strategies and work processes. Inhibiting factors included organisational instability, overreliance on event-based activities, insufficient collaboration with volunteer organisations, and a consistent absence of systematic evaluation across all municipalities.</p> Conclusions <p>ABC, when implemented successfully, offers a flexible, recognisable, and accessible framework that can contribute to healthier settings for both employees and citizens. ABC is most successful when integrated into already existing systematic public health strategies. Successful implementation requires structural anchoring, long-term commitment, and robust evaluation mechanisms to ensure sustainable impact.</p>