Integrating implementation science and health policy research addresses the know-do gap in LMIC healthcare systemsBridging Research and Policy to Improve Health in Developing Nations

This narrative and conceptual review examines the interface between implementation science and health policy research. Drawing on literature from both disciplines, we analyze key areas of convergence and divergence, explore how these distinctions contribute to the persistent ‘know-do gap,’ and discuss opportunities for integrated approaches connecting micro-level implementation processes with macro-level policy dynamics, with particular attention to LMICs. Implementation science and health policy research have evolved largely in parallel, despite sharing a common objective: improving population health by translating knowledge into action. Implementation science focuses on integrating evidence-based interventions into real-world settings, while policy research examines how policies are formulated, adopted, and sustained within complex political systems. This disciplinary separation has contributed to a persistent “know–do gap,” particularly in low-and middle-income countries (LMICs), where fragmented health systems, political economy constraints, and donor influence shape both policy trajectories and implementation realities. The disconnect between researchers and policymakers often stems from differing timing, priorities, and even language. Researchers may not address the immediate concerns of policymakers, and scientific evidence alone seldom drives policy changes. In LMICs, this divide is exacerbated by political cycles, vested interests, and the significant influence of international donors. In this review, we argue that bridging implementation science and policy research is not merely desirable but necessary. We examine how differences in scope, actors, settings, and theoretical frameworks have reinforced this divide, and we propose the development of integrated, hybrid approaches that connect micro-level implementation processes with macro-level policy dynamics. Bridging the gap between implementation research and policy change necessitates a context-sensitive approach that acknowledges the complexities of political, economic, and social systems, particularly in LMICs. By leveraging multi-level frameworks, engaging stakeholders, and fostering continuous learning, it is possible to enhance the translation of research into effective, sustainable health policies.