Telecollaboration environments provide language learners with rich opportunities for natural and authenticated communication. Web 2.0 tools from blogs to videoconferencing to 3D virtual worlds are used to form new social environments for collaborative creation, sharing and exchange. Real-life communication has thus expanded into virtual space with unprecedented possibilities for natural and incidental language learning outside and beyond the traditional classroom. In my talk, I will demonstrate and discuss the pedagogical potential of telecollaboration for monolingual and multilingual communication practice with reference to the European projects TILA and IVY/EVIVA. The TILA project ("Telecollaboration for Intercultural Language Acquisition") focuses on foreign language learning in secondary and tertiary education. The aim is to use the 3D virtual world environment OpenSim and the web 2 videoconferencing environment BigBlueButton to facilitate and foster intercultural communicative interaction and competence development in tandem and lingua franca constellations. In the IVY/EVIVA project ("Interpreter Training in Virtual Reality") virtual scenarios in SecondLife are used to provide interpreter students with opportunities for independent and authentic interpreting practice.