Although the public–private partnerships in health have been adopted as the best pathway to improving health outcomes in many developing nations, implementation lacks collaborative leadership. The purpose of this empirical qualitative case study was to determine key factors that promote leadership synergy (LS) between partners that enhance ownership and accountability of community health and social initiatives in Tanzania. The diffusion of innovation theory and public–private integrated partnership module were the theoretical framework guided this study. Diffusion of innovation theory is based on the importance of effective communication to spread new ideas and foster change in behavior in a social group such as public and private partnership integrations (Roger, 2003). Twenty-six participants responded to in-depth, one-on-one interviews and the related documents were reviewed. With the use of directed content analysis and NVivo program, six themes emerged. Findings confirmed that integrated supportive supervision, teamwork, and strategic communications promote partnership LS. On the other hand, findings also showed that unclear roles and responsibilities, weak data, and limited understanding of the benefits of public–private partnerships at the community level hinder ownership and accountability. The potential positive social change of this study includes improving LS that promotes community leader engagement and ultimately improving access and use of community health and social programs in Tanzania.