This book constitutes the thoroughly refereed post-conference proceedings of the 9th International Workshop on Engineering Societies in the Agents World, ESAW 2008, held in Saint-Etienne, France, in September 2008.

The 13 revised full papers presented together with 1 invited long paper were carefully selected from 29 submissions during two rounds of reviewing and revision. The papers are organized in topical sections on organisations and norm-governed systems, privacy and security, agent-oriented software engineering, emergence and self-organisation, as well as simulation.