In 2004 Flanders, the northern region of Belgium launched a range of large public-private partnership (PPP) projects for a total value of 6 billion euros. Ten years later, PPP has become a well-embedded procurement method for long-term public infrastructure projects. This article makes a critical round-up of PPP experience in Belgium based on the perspectives of infrastructure professionals who were asked to provide their views on performance-related issues in PPP projects. Two workshops were held to further enrich the input and ideas. Based on this empirical material this article formulates 10 lessons to improve PPP performance, which is deliberately broadly defined. It argues that the dominant value for money evaluations, following strictly financial or commercial logics (in both the private and public sectors), need to be broadened. Given the large impact and cost of large infrastructure projects on society, broader societal and spatial contributions of PPPs are needed.