With the development of new digital technologies and their gradual introduction into the language classroom, the Internet enables students to reach out beyond the confines of traditional teaching and learning settings, allowing previously non-existent access to foreign languages and cultures. In telecollaborative exchanges, for example, language students use online tools to establish contact with other learners of the target language and native speakers. The learning environments for such encounters are becoming increasingly more powerful, often combining different modes of communication in one single medium, the learners' PC. In 2005, students of French at Carnegie Mellon University, US and French learners at the Open University, UK worked synchronously and asynchronously in online environments with native francophone students enrolled on a masters program in distance education at the Université de Franche Comté, France. Completing a set of three collaborative tasks, synchronous meetings took place over 10 weeks in the Open University's Internet-based audio-graphic tuition environment Lyceum, which provides multiple synchronous audio channels as well as synchronous text chat and several shared graphical interfaces. The project output, a shared reflection on cultural similarities and differences, took the form of several collaborative, asynchronous blogs. This contribution draws on data from pre-and post-treatment questionnaires, recordings of the online interactions, work published by the students in the blogs and discussions among learner and tutor participants exploring aspects of online partnership learning such as learning environment-specific affordances and their impact on task design as well as learner interaction .