This study involved 377 ERASMUS students from the University of Oviedo in an academic year. An ad-hoc questionnaire was applied in on-line format to determine students' perceptions and opinions and to understand the motivations that impel them to participate in these activities and their degree of satisfaction. The study analyzes the process of Erasmus mobility, noting that, as a result of the stay, the students describe their mastery of the host country language as good or excellent in most cases. Academic and cultural factors, the desire to get to know a new environment and to have a European experience impel most of the students to travel abroad. Job prospects are another motivating factor, and the overall assessment of the planned stay is acceptable, good or excellent in most cases.