Three decades of public-private partnerships (PPPs) have witnessed significant evolution in policies and practices. However, the critical success factors for PPPs influence their early and late stages differently. Natural experiments provide one of the best settings to identify these differences. This paper exploits one such instance in the context of road project up gradations in India. The fundamentals established by the first road PPP project in India were completely revamped during the re-conceptualization of the project twenty-five years later. Comparing and contrasting the two projects provided evidence of the differences in the influence of critical success factors at the two stages. At the institutional level, the findings reflect an evolution in motivations, maturity in regulatory frameworks, and changes in performance perceptions. Significant differences between the PPP models deployed in the two stages were also found. The government's willingness to take greater financial and economic risks were found to drive these changes. Upon comparison with the existing literature, this conclusion is indicative of different drivers of change in business models across emerging economies. © 2020 The Authors. Published by Elsevier B.V.