This book constitutes revised selected papers from the refereed proceedings of the 20th International Conference of the Italian Association for Artificial Intelligence, AIxIA 2021, which was held virtually in December 2021. The 36 full papers included in this book were carefully reviewed and selected from 58 submissions; the volume also contains 12 extended and revised workshop contributions. The papers were organized in topical sections as follows: Planning and strategies; constraints, argumentation, and logic programming; knowledge representation, reasoning, and learning; natural language processing; AI for content and social media analysis; signal processing: images, videos and speech; machine learning for argumentation, explanation, and exploration; machine learning and applications; and AI applications.

This book constitutes the revised and selected papers from the 6th International Workshop on Engineering Multi-Agent Systems held in Stockholm, Sweden, in July 2018, in conjunction with AAMAS 2018. The 17 full papers presented in this volume were carefully reviewed and selected from 32 submissions. The book also contains a state-of-the-art paper that reflects on the role and potential of MAS engineering in a number of key facets. The papers are clustered around the following themes: programming agents and MAS, agent-oriented software engineering, formal analysis techniques, rational agents, modeling and simulation, frameworks and application domains.

This book constitutes the thoroughly refereed post-proceedings of the 10th International Workshop on Declarative Agent Languages and Technologies, DALT 2012, held in conjunction with the 11th International Joint Conference on Autonomous Agents and Multiagent Systems (AAMAS 2012) at Valencia, Spain, in June 2012. The volume contains 13 revised selected presented at DALT 2012.The papers cover the following topics: declarative languages and technologies, computational logics, declarative approaches to engineering agent-based systems, models of business interactions among agents, and models of trust, commitments, and reputation for agents.