Tallinn University (TLU) is the third largest public university in Estonia with 9500 students in 20 institutes and five colleges. The Centre for Educational Technology (CET), established in 1998 is an interdisciplinary R&D unit within the Institute of Informatics of TLU. International staff of CET (25 in total) consists of 14 full-time researchers, 6 software developers, 4 post-doc researchers, some part-time employees and a group of postgraduate students. Scientific and technological qualifications of CET staff intertwine deep knowledge in educational research, open-source software engineering, and experiences of empirical research in authentic educational and work settings in the field of technology enhanced learning, competency management, interactive media art, interaction design and Semantic Web technologies. The main research projects in CET are related with research-based development of the next-generation distributed learning environments involving interoperable social software tools (personal learning environments, e-portfolio, learning object repository and QTI test authoring/delivery tools) and Web services.