This study looked at 12 projects on payment for environmental services (PES) from four countries where it has been applied. Results show that most of the projects have had a positive impact both on the environment and on people’s livelihoods and their awareness of the value of natural resources and environmental services. However, the study recommends that, to make PES projects more effective in the future, steps need to be taken to secure land tenure and to establish a clear PES implementation framework. Such a framework should address issues such as service evaluation, legal support, finance, and social capacity.