The development of multiagent systems (MAS) is not a trivial task. In addition, with the advances in Internet technologies, MAS are undergoing a transition from closed to open architectures composed of a huge number of autonomous agents, which operate and move across different environments. In fact, openness introduces additional complexity to the system modeling, design and implementation. It also impacts on most quality attributes of MAS, including scalability, interoperability, reliability and adaptability. This paper brings together researchers and practitioners to discuss the current state and future direction of research in software engineering for open MAS. A particular interest is to understand those issues in the agent technology that make it difficult and/or improve the production of large open systems.