The rapid growth of private participation in infrastructure (PPI) in developing countries during the 1990s was followed by a subsequent decline in investments and the re-negotiation and cancellation of some projects. This work explains the factors behind the growth and decline of PPI, its impact and the policy lessons that have been learnt from this experience. It concentrates on the experience with the private provision of infrastructure from the 1990s. The text assesses the impact that the private provision of infrastructure has had on service delivery. It also reviews the main policy lessons that can be drawn, and what governments need to do moving forward if they are to ensure that the supply of infrastructure service does not become an impediment to growth.