Ecosystem services (ES) are increasingly used as the conceptual driver for conservation and development actions, largely following from the influential Millennium Ecosystem Assessment. Scholars skeptical of the neoliberal turn in conservation have critiqued the use of economic values for nature’s services. What has been less well understood and reviewed, however, is how concepts of ES are enacted by technologies of calculation, as well as how calculative practices move through networks and among stakeholders. This review traces how definitions and metrics of ES have evolved and how they are used, such as in biodiversity offsetting and wetland mitigation programs. Using the idea of the creation and deployment of calculative mechanisms, this article discusses how these processes proceed in different ES contexts, assesses what work has to happen ontologically to make ES commensurable and circulatable, and speculates on what the opportunities for future pathways other than commodification are.