Objectives: Public-private associations (PPPs), for the government sector, an opportunity to take advantage of the experience and efficiency of the private sector to improve the representation of services and develop the necessary infrastructures for economic and social development. PPPs generally involve large-scale projects, but unfortunately some sectors, such as water management, exclude the opinion of experts, giving rise to monopolies that greatly benefit the private sector, even excluding them from responsibilities by not fully resolving the problem for which they were created. contracted, the costs being absorbed by the public sector. Methodology: Confirming the success of PPP participation in works still in operation is premature, but an analysis of the current results is made, taking as a case study, the "Agua Prieta" Wastewater Treatment Plant (PTAR). Contribution: The results show that the collaboration of community groups in carrying out a participatory diagnosis and having follow-up and evaluation mechanisms to monitor the performance of the private partner, are actions that further improve the chances of success of the project; On the other hand, competition and the adequate selection of private partners represent the biggest failure factor in the implementation of PPPs.