• The Common Agricultural Policy (CAP) severely impacts biodiversity and ecosystem services. • Main environmental constraints and opportunities need to be better accounted for by the CAP. • Considering ecological thresholds is key to mainstreaming biodiversity and ecosystem services. • Reforms should increase policy coherence and adopt mixes of policy instruments. The European Union's Common Agricultural Policy (CAP), being one of the strongest drivers of agricultural land-use practices, has a substantial impact on biodiversity and ecosystem services in the Member States. The initial focus of the CAP to increase and intensify agricultural production affected water and land qualities and contributed to the degradation of traditional agricultural landscapes, cultural identities, and erosion of typical farmland biodiversity. Recent CAP reforms have begun to consider biodiversity and ecosystem services, but still fall short of a thorough mainstreaming approach. The objectives of this paper are to point out main findings regarding (i) key shortcomings of the current CAP, and (ii) major opportunities to enhance the mainstreaming of biodiversity and ecosystem services within the CAP. The paper is based on insights generated in the sub-global assessment of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) for Europe and Central Asia 1 1 A major part of this contribution is based on an earlier, pre-peer reviewed version of Ring et al. (2018) : Ring, I., Sandström, C., Acar, S., Adeishvili, M., Albert, C., Allard, C., Anker, Y., Arlettaz, R., Bela, G., ten Brink, B., Fischer, A., Fürst, C., Galil, B., Hynes, S., Kasymov, U., Marta-Pedroso, C., Mendes, A., Molau, U., Olschewski, R., Pergl, J., & Simoncini, R. (2018): Chapter 6: Options for governance and decision-making across scales and sectors. In: IPBES (2018): The IPBES regional assessment report on biodiversity and ecosystem services for Europe and Central Asia. Rounsevell, M., Fischer, M., Torre-Marin Rando, A., Mader, A. (eds.). Secretariat of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, Bonn, Germany, pp. 661-802.. Our results illustrate the evolution of agricultural policy objectives and instruments applied in the CAP, and their effects on selected ecosystem services and biodiversity. We shed light on key shortcomings of existing policy and provide recommendations for further CAP reforms to achieve more effective biodiversity conservation and sustainable use of ecosystem services. [ABSTRACT FROM AUTHOR]