Abstract Improving public health outcomes requires more than the delivery of services; it demands sustainable behavioural transformation within individuals, families, and communities. Social and Behaviour Change Communication (SBCC) has emerged as a critical strategy for promoting healthy practices, improving health service utilization, and strengthening community engagement. This paper examines the theoretical foundations, implementation strategies, and practical applications of SBCC in community health and nutrition programs. It synthesizes concepts such as the ecological model, behavioural determinants, the P-Process framework for communication planning, and behavioural economics approaches including Nudge theory. Drawing on community health experiences and case examples from maternal health, child nutrition, tuberculosis treatment adherence, adolescent health, and hygiene promotion, the paper highlights the importance of culturally sensitive communication, multi-level interventions, and participatory community engagement. The findings suggest that SBCC strategies that integrate interpersonal communication, community mobilization, and policy-level support can significantly improve health behaviours and outcomes. Strengthening frontline worker capacity and leveraging behavioural insights can ensure sustainable and scalable public health interventions. The paper concludes with recommendations for integrating SBCC within national health systems and community-based health programs.