摘要:Major investments by development partners in low- and middle-income countries (LMICs) often seek to develop a supportive policy environment. There is limited knowledge about the mechanisms that development partners use to influence government policy, or which mechanisms are effective. This study assessed the influence of Avahan, a large HIV/AIDS prevention program in India supported by the Bill and Melinda Gates Foundation, on the development of HIV/AIDS policies in India, particularly the National AIDS Control Program III (NACP III). A retrospective assessment of the contributions of Avahan to the development of NACP III was conducted based upon document review and in-depth interviews with key informants, including Avahan staff and staff of implementing partners. This assessment was carried out within a framework centered on three domains: evidence considered by policy and decision-makers; the channel through which influence is exerted; and the target audience for influence. Respondents identified a number of respects in which Avahan influenced NACP III policy, notably, Avahan influenced perception of the feasibility of scaling up services (through a demonstration effect) and Avahan, along with others, helped ensure a strong focus on targeted interventions. Overall Avahan’s influence was greatest during policy implementation. While the extent to which research evidence generated by Avahan influenced NACP III was limited, best practice evidence generated by Avahan, including the lessons learned from routine implementation and management, contributed significantly to NACP III. This was largely due to the credibility Avahan had established and strategic ‘inside track’ communications. While studies of knowledge translation typically focus primarily on scientific evidence, this study suggests that other forms of evidence, notably best practice evidence derived from program experience, and disseminated through personal communication, were particularly influential. The framework developed for the paper provides a useful tool to analyze how evidence-based influence is exerted.