Public Private Partnerships (PPP) were introduced in emerging economies in the 1990s, with Latin American countries taking the lead. PPPs for this report include all types of private participation, whether there is or is not financial contributions by the government, the so called concessions or PPP in certain countries and Private Finance Initiatives (PFI). There is over 25 years of experience and more than 7000 projects implemented as PPP (Guasch, 2016). The findings, here presented, are based on an analysis of over 1500 concessions/PPP around the world and on the analysis of a large number of PPP programs (legal, project selection, institutions, procurement, procedures, oversight and conflict resolutions). The report shows that indeed PPP programs have been and can be quite effective to complement public works in breaching the infrastructure gap and the quality of public services. Yet, it is not automatic, and a number of things and elements have to be in place to secure the expected benefits. While PPP programs can be quite effective, they have also weaknesses that need to be addressed, the main one being their vulnerability to contract renegotiation. The incidence of contract renegotiation is staggering and can threaten the credibility of the program. A key focus of this report is to illustrate and analyze the incidence and tendencies of contract renegotiation. Plenty of mistakes have been made but most of them can be relatively easily corrected if there is the appropriate commitment, leadership, knowledge and capacity in place. PPP programs have to evolve, and many of them are doing so to reach the stage needed to secure the extensive benefits of PPP.