Tony Ross-Hellauer is the OpenAIRE2020 Scientific Manager at Göttingen State and University Library (University of Göttingen). In its mission to further Open Science, OpenAIRE has investigated those models of peer review that are counted as “Open Peer Review” (OPR). A first step was to collect, categorize, analyze and evaluate the manifold definitions of the concept of Open Peer Review. At this poster session Tony reported about this phase and its outcomes.