<p>This book constitutes the refereed proceedings of the&nbsp;27th International Workshop on Coordination, Organizations, Institutions, Norms, and Ethics for Governance of Multi-Agent Systems,&nbsp;COINE&nbsp;2023, held in&nbsp;London, UK, on May 29,&nbsp;2023&nbsp;(co-located with 22nd International&nbsp;Conference on Autonomous Agents and Multi-Agent Systems (AAMAS)).<br></p><br></p><p>This book&nbsp;contains 10 full&nbsp;papers which are the extended and revised versions&nbsp;of the papers accepted to the workshop.</p><p>The papers were&nbsp;carefully reviewed and&nbsp;selected from&nbsp;13&nbsp;submissions. They are organized in topical sections as follows:&nbsp;Norms, Social contracts, Institutions,&nbsp;and Privacy; Studies on the notion of Value; and Argumentation and&nbsp;Conventions</p>