To determine whether the medical school grades of today's professors at the Zagreb University School of Medicine could serve as the predictors of their subsequent academic success.We performed a retrospective descriptive study of medical school grades of professors and/or assistant professors at the Zagreb University School of Medicine from 1990 to 2003. The professors were divided into four groups according to the course they taught: Basic Science, Clinical Non-Surgery, Clinical Surgery, and Public Health. In total, data for 297 professors were analyzed.Today's professors were above-average students. The analysis of grades of professors teaching different disciplines revealed that Basic Science professors were the best students, followed by Non-Surgery and Surgery professors, whereas Public Health professors were the worst. Grades that professors earned in Public Health courses were the highest, followed by grades in Non-Surgical and Surgical courses. The grades in Basic Science courses were the lowest.Professors at the Zagreb University School of Medicine were above-average students and their grades seem to be important predictors of future success in academic career. Among today's professors, Basic Science professors were the best students.