Although the public-private partnership (PPP) concept in health and social health has been politically accepted as the best pathway to improving health outcomes in many developing nations, implementation lacks leadership synergy. Lack of awareness and engagement of community leaders about PPP interventions and their benefits affect accountability and ownership of health and social care interventions. The purpose of this study was to better understand factors that could promote partnership leadership synergy to enhance ownership and accountability for community health and social welfare initiatives in Tanzania. A qualitative empirical case study design was used; diffusion of innovation and the public-private integrated partnership module constituted the theoretical framework. A purposeful sample of 26 participants responded to in-depth, 1-on-1 interviews; they were guided with semi-structured questions; the related document was reviewed. NVivo software was used to facilitated data management and content analysis. The key findings indicated that integrated supportive supervision, teamwork, and strategic communications promote partnership leadership synergy. Also, findings show that a lack of clear roles and responsibilities, poor quality data, a lack of understanding the benefits of PPP in health at the community level hinder ownership and accountability in the implementation of PPP health interventions. The results of this study yield insight into the national PPP technical and leadership team that could support the priorities in the implementation of the partnership projects. These results may contribute to social change through an increase in awareness and understanding of PPP in health at the community level and, in turn, promote ownership and accountability.