Abstract. Open source software has become a common way of disseminating research results. In this talk, we first introduce the motivations and implications of releasing research prototypes as open source software (OSS). ObjectWeb is an international consortium fostering the development of open source middleware. We give an overview of tools available for OSS development and management based on ObjectWeb experiences. The infrastructure required for hosting such developments is also described. We report various experiences and practices of small and large ObjectWeb projects in their way to reach the quality of industrial strength products. Finally, we summarize the lessons learned from the success and failures of these projects.