Target 2, Action 5 of the EU Biodiversity Strategy requests member states “to map and assess ecosystems and their services” (Mapping and Assessment of Ecosystems and their Services – MAES initiative). The objective of this paper is to present and discuss the preliminary outcomes of the approach taken to define indicators for implementing MAES in Germany. The paper introduces the requirements for using indicators from a perspective of nature conservation policy, in particular the need to discern the demand and supply of ecosystem services, including their potentials, actual and future use, as well as the natural contributions and human inputs to the generation of ecosystem services. An adapted, differentiated, ecosystem services terminology is presented and a first set of indicators is introduced and explained. The paper closes with an estimate of potential benefits of information produced by implementation of a national MAES for various fields of policy (e.g. local and regional landscape planning) and proposes some recommendations for further research and practical exploration.