Peer review is a cornerstone of science, whose quality and efficiency depends on a complex, large-scale collaboration process, which is sensitive to motivations, incentives and institutional contexts. Recent proofs of the failures of peer review, due to judgment bias and parochialism and cases of misconduct, have contributed to calls for a reconsideration of the rigour and quality of the process. This Action aims to improve efficiency, transparency and accountability of peer review through a trans-disciplinary, cross-sectorial collaboration. The objectives of this Action are: (i) to analyse peer review in different scientific areas by integrating quantitative and qualitative research and incorporating recent experimental and computational findings; (ii) to evaluate implications of different models of peer review and to explore new incentive structures, rules and measures to improve collaboration in all stages of the peer review process; (iii) to involve science stakeholders in data sharing and testing initiatives, (iv) to define collaboratively a joint research agenda that points to an evidence-based peer review reform. Not only can a better peer review system improve the self- regulation processes of science to benefit all science stakeholders, it can also increase the social recognition and credibility of science in Europe.