This book constitutes the refereed proceedings of the 11th International Conference of the
Italian Association for Artificial Intelligence AI*IA 2009 held in Reggio Emilia Italy in
December 2009. The 50 revised full papers presented together with 3 invited talks were
carefully reviewed and selected from 83 submissions. The papers are organized in topical
sections on knowledge representation and reasoning machine learning evolutionary computation
search natural language processing multi-agent systems and application.
