The ATOP (Agent-Based Technologies and Applications for Enterprise Interoperability) workshop series focuses on technologies that support interoperability in networked organizations, on successful applications of these technologies, and on lessons learned.

Business Interoperability.- Vertical Information Integration for Cross Enterprise Business Processes in the Energy Domain.- Agents for Cross-Organisational Business Interoperability.- Organizations and Virtual Institutions.- Enhancing Interoperability: Ontology-Mapping in an Electronic Institution.- Emergent Process Interoperability within Virtual Organisations.- Analysis and Support of Organizational Performance Based on a Labeled Graph Approach.- Adding Organisations and Roles to JADE with JadeOrgs.- Modeling Multiagent Systems.- Interoperability with Goal Oriented Teams (GORITE).- The Platform Independent Modeling Language for Multiagent Systems.- Agent Interaction.- Enhancing UML to Formalize the FIPA Agent Interaction Protocol.- Modeling Interaction Protocols as Modular and Reusable 1st Class Objects.- Agent Interaction Modeling Based on Product-Centric Data: A Formal Method to Improve Enterprise Interoperability.- Security.- Security Aspects on Inter-organizational Cooperation Using Wrapper Agents.- Agent-Community-Network-Based Secure Collaboration Support System.

The ATOP (Agent-Based Technologies and Applications for Enterprise Interoperability) workshop series focuses on technologies that support interoperability in networked organizations, on successful applications of these technologies, and on lessons learned. So far two ATOP workshops have been held at the AAMAS conferences in Utrecht, The Netherlands, in July 2005, and in Estoril, Portugal, in May 2008. The 13 papers presented here are extended versions of carefully reviewed and selected contributions to the workshops. The topics covered are business interoperability; organizations and virtual institutions; modeling multiagent systems; agent interaction; and security. The main goal was to collect approaches for the application of agent technologies in these areas. Current trends in the development of agent technologies are compared with recent developments in service-oriented and model-driven system design, with respect to their ability to solve interoperability problems.