Payments for environmental services (PES) have been distinguished from the more common integrated conservation and development projects on the grounds that PES are direct, more cost-effective, less complex institutionally, and therefore more likely to produce the desired results. Both kinds of schemes aim to achieve similar conservation outcomes, however, and generally function in analogous social, political and economic environments. Given the relative novelty of PES, what lessons can be learnt and applied from earlier initiatives? In this paper, we describe the evolution over the first 12