This article reports on a quasi-experimental investigation with a pre-test/post-test control group design carried out in the second semester of the academic year 2006-2007 with Spanish pre-service English teachers at the University of Jaen in Spain. Its aim was to determine whether the use of virtual learning environments (VLE) and computer-mediated communication (CMC) within the European Higher Education Area (EHEA) could improve the teacher trainees' lexical competence. After outlining the rationale of the initiative, grounded on previous research outcomes and on the novelty of the experience, this article describes the actual project and study. It outlines the semantic fields, lexical aspects, vocabulary learning strategies, and activity types on which the project has focused and goes on to describe the research design and procedure of the investigation. It subsequently presents and discusses the results yielded by the latter. The limitations of the study, together with the lines for future research and the consequences which the project has had, are broached in the final section of the article. (Contains 7 tables and 4 figures.)