This book constitutes the thoroughly refereed post-workshop proceedings of the 8th International Workshop on Declarative Agent Languages and Technologies, DALT 2010, held in Toronto, Canada, on May 10, 2010, as a satellite workshop of the 9th International Joint Conference on Autonomous Agents and Multiagent Systems, AAMAS 2010.The 7 revised full papers presented together with 4 invited lectures were carefully selected during two rounds of reviewing and improvement from 24 initial submissions. DALT aims to make formal methods and declarative technologies and approaches available to and...

This book constitutes the thoroughly refereed post-proceedings of the 9th International Workshop on Declarative Agent Languages and Technologies, DALT 2011, held in Taipei, Taiwan, in May 2011. The volume contains 6 revised selected presented at DALT 2011, 7 best papers from the DALT series over the years, explaining how the research developed and how it influenced and impacted the community, the state-of-the-art and subsequent work, and two invited papers from the DALT Spring School, which took place in April 2011.