In the coming years, public-private partnerships (PPPs) should play an increasingly relevant role as an important alternative for financing projects and infrastructure in public services. However, especially in public health, PPPs are not always a good alternative, since they may introduce distortions in the agenda that sets health needs, favoring companies' interests. Public agencies can benefit from collaboration with the private sector in areas where there is a lack of specialization, such as the development of research and technologies. Even in these cases, each institution's role needs to be defined in order to avoid conflicts of interest. This can be challenging when dealing with the formulation of public and regulatory policies, on the impacts of certain policies, especially in developing countries. To engage with the private sector without compromising the integrity of government actions requires a broad discussion by public health stakeholders, for clear reasons of conflicting visions and scopes between corporations and public health. Combined with this is the need for multi-sector approaches, with a high load of financial investments in the various dimensions of policies to control the most prevalent diseases, especially chronic non-communicable diseases (NCD). This article classifies PPPs in categories in order to minimize the potential risks of conflicts of interest than can impact public health. These categories are defined as possible, possible with caveats, and impossible for involvement with certain institutions.