Web-based Three-dimensional collaborative and impressive Virtual Learning Environments (VLE) offer considerable promise for the design of effective constructivist learning environments. Collaboration within a VLE enables learners to carry out tasks in groups, which offers beside the knowledge exchange a platform for training social competences and teamwork capabilities. In this paper, the design and concept of a new framework called "Modular virtual Learning World" (MLW) is described. MLWs are collaborative and immersive VLEs and offer modular and customizable solutions to enhance VLE building process for enterprise training and vocational training. An ongoing project called "Virtual Car Dealer" (VAH, in German "Virtuelles AutoHaus") based on the MLW is also presented. It is designed to support German vocational training system. In addition, different aspects of VAH like pedagogical support, virtual learning environment and learning scenario are described.
