Abstract. Over the last years, several repositories have been proposed in response to the need of the MDE community for advanced systems supporting the reuse of modeling artifacts, and the adoption of model management tools as software-as-service. Even though the potential benefits of MDE repositories are valuable, researchers and practitioners seem to prefer the management of their modeling artifacts locally and do not use yet advanced mechanisms for sharing and reusing them. This paper discusses the opportunities related to the adoption of model repositories and identify research issues that have to be addressed in order to make model repositories a reality in MDE.