ThesearetheproceedingsoftheInternationalWorkshoponProgrammingMulti- Agent Systems (ProMAS 2008), the sixth of a series of workshops that is aimed at discussing and providing an overview of current state-of-the-art technology for programming multi-agent systems. The aim of the ProMAS workshop series is to promote research on progr- ming technologies and tools that can e?ectively contribute to the development and deployment of multi-agent systems. In particular, the workshop promotes the discussion and exchange of ideas concerning the techniques, concepts, - quirements, and principles that are...