This book constitutes the thoroughly refereed post-workshop proceedings of the First International Workshop on Languages, Methodologies and Development Tools for Multi-Agent Systems, LADS 2007, held in Durham, UK, in September 2007. The workshop was part of MALLOW 2007, a federation of workshops on Multi-Agent Logics, Languages, and Organizations.

Invited Paper.- Open Knowledge.- Agent Reasoning and Semantics.- Probabilistic and Logical Beliefs.- An Argumentation Based Semantics for Agent Reasoning.- Goal Selection Strategies for Rational Agents.- Declarative Languages and Technologies.- A Common Basis for Agent Organisation in BDI Languages.- Adjusting a Knowledge-Based Algorithm for Multi-agent Communication for CPS.- Methodologies and Design.- Extending the MaSE Methodology for the Development of Embedded Real-Time Systems.- Measuring Complexity of Multi-agent Simulations – An Attempt Using Metrics.- DCaseLP: A Prototyping Environment for Multi-language Agent Systems.- A Step Towards Fault Tolerance for Multi-Agent Systems.- Development Frameworks.- The Webbridge Framework for Building Web-Based Agent Applications.- Specifying Interaction Space Components in a FIPA-ACL Interaction Framework.- Enabling the Reuse of Platform-Dependent Agents in Heterogeneous Agent-Based Applications.- Introducing a Process Infrastructure for Agent Systems.- Facilitating Agent Development in Open Distributed Systems.- simpA: A Simple Agent-Oriented Java Extension for Developing Concurrent Applications.

This book constitutes the thoroughly refereed post-workshop proceedings of the First International Workshop on Languages, Methodologies and Development Tools for Multi-Agent Systems, LADS 2007, held in Durham, UK, in September 2007. The workshop was part of MALLOW 2007, a federation of workshops on Multi-Agent Logics, Languages, and Organizations. The 15 revised full papers, presented together with 1 invited paper reporting the aims and achievements of the OpenKnowledge project, were carefully reviewed and selected from 32 submissions. The papers are organized in topical sections on agent reasoning and semantics, declarative languages and technologies, methodologies and design, and development frameworks.