Multilingualism in education is a conceptual as well as a pedagogical challenge of the 21st century. Luxembourg, with its three statutory official languages (Luxembourgish, French and German), is an especially complex setting. The gap between traditional principles of language education on the one hand and the challenging impacts of today's multilingualisms on the other led the University of Luxembourg (founded in 2003) to set up a developmentally-driven Master's programme in 2007, entitled "Learning and Development in Multilingual and Multicultural Contexts". After a presentation of the general multilingual settings in Luxembourg, this paper discusses the constellation of the multilingual University's staff and students and provides an analysis of the concept of the course by outlining its innovative approach, its principles and lessons learned with regard to running a trilingual higher education programme.