This volume is the ?fth in a series that started in 2005, collecting papers from the Coordination, Organizations, Institutions and Norms (COIN) Workshops. The papers in this volume are drawn from the three meetings that took place in 2009. AAMAS COIN@AAMAS 2009 took place on May 12, 2009, as a satellite event of the 8th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2009), in Budapest, Hungary. With 35 registered participants, the workshop was an exciting and fruitful gathering where discussions followed the papers presented by an international group of speakers....

This book constitutes the thoroughly refereed post-conference proceedings of the 12th International Workshops on Coordination, Organizations, Institutions and Norms in Agent Systems, COIN 2016. The workshop COIN@AAMAS 2016 was held in Singapore, Singapore, in May 2016, and the workshop COIN@ECAI 2016 was held in The Hague, The Netherlands, in August 2016.

The 9 full papers were carefully reviewed and selected from 15 submissions for inclusion in this volume. They cover the following topics:
Social Issues: The papers focus on the security of personal data, support for...