Background: Residency work hour restrictions in 2003 changed medical student participation in overnight call. Purposes: The goal is to compare experiences, attitudes, and skills between medical students who did and did not participate in overnight call. Methods: Using a retrospective cohort design, all students at one medical school received a survey at the end of their 3rd-year internal medicine clerkship. Students at 3 clerkship sites were required to take overnight call, and students at 2 sites were not. Results: One hundred four of 167 (62%) students participated. Sixty-one of 104 (59%) took overnight call. Overnight call students reported improved team relationships and were able to evaluate more unstable "cross-cover" patients. Students who took overnight call were more likely to state it was worthwhile (58% vs. 34%; p =.034). Overnight call led to fatigue and the perception of interference with didactics. Conclusions: Overnight call within the internal medicine clerkship has positive and negative effects. With new residency work hour restrictions, schools may consider innovative ways to preserve the positive experiences while working to minimize fatigue and interference with learning.