The aim of this longitudinal study was to investigate differences in interests, personality, and cognitive abilities between students majoring in the six specialties of psychology at the University of Amsterdam. Results show that students at Social Psychology and Work and Organizational Psychology were on average more extraverted than students of other specializations, that students of Psychological Methods and Psychonomics were relatively more open to experience, and that students at Clinical Psychology were on average more neurotic. Differences in cognitive ability were small, but significant, with the highest scores among students of the more research-oriented specialties. With discriminant analyses on the basis of nine interest scales, 53% of the students were correctly categorized in the specialization chosen two or years after interests were measured. Interest profiles of the specialties follow differences in interest in helping people, abstract vs. concrete topics, and technical issues. Person-specialization congruence failed to predict academic performance. (Contains 3 tables and 3 figures.)