Purpose: To evaluate the effectiveness of medical Spanish instruction by assessing Spanish language comprehension in physician assistant (PA) education. Methods: We performed a retrospective analysis of Spanish pretest and posttest performance for all PA students who completed the University of Texas Southwestern (UTSW) PA Program between 2004 and 2008 (N = 171). The intervention involved having each student complete five credit hours (75 contact hours) of medical Spanish over three semesters. Results: The mean examination performance of all classes combined improved by 11.5%. This difference of the means was statistically significant (95% Cl = 10% to 13%; paired t-test, t = 14.96; P < 0.0001). Each of the five classes improved; however, the mean examination scores of nonnative speakers improved more than those of native speakers. Conclusions: Medical Spanish instruction to PA students provides a basis for the development of foreign language competency for use in the clinical setting.