Medical schools can assist students by providing them with quality career counseling to help them choose a medical specialty. Many schools use interest inventories to help identify students' specialty interests. This study examined the predictive validity of one such inventory, the Medical Specialty Preference Inventory (MSPI). In a longitudinal design, we used discriminant function analysis to examine how well students' scores on the MSPI fit their chosen medical specialty one year later. The MSPI correctly predicted students' future medical specialty choice 58.1% of the time. These results can help career advisors interpret MSPI scores, and identify students' most likely medical specialty choice, as well as their second most likely choice. (Contains 1 figure and 2 tables.)