Costa Rica pioneered the use of the payments for environmental services (PES) approach in developing countries by establishing a formal, country-wide program of payments, the PSA program. The PSA program has worked hard to develop mechanisms to charge the users of environmental services for the services they receive.

Payments for environmental services (PES) are an innovative approach to conservation that has been applied increasingly often in both developed and developing countries. To date, however, few efforts have been made to systematically compare PES experiences.

Payments for environmental services (PES) have attracted increasing interest as a mechanism to translate external, non-market values of the environment into real financial incentives for local actors to provide environmental services (ES). In this introductory paper, we set the stage for the rest of this Special Issue of Ecological Economics by reviewing the main issues arising in PES design and implementation and discussing these in the light of environmental economics. We start with a discussion of PES definition and scope.

This paper examines the main ways in which Payments for Environmental Services (PES) might affect poverty. PES may reduce poverty mainly by making payments to poor natural resource managers in upper watersheds. The extent of the impact depends on how many PES participants are in fact poor, on the poor’s ability to participate, and on the amounts paid. Although PES programs are not designed for poverty reduction, there can be important synergies when program design is well thought out and local conditions are favorable.