BACKGROUND: In the present milieu of rapid innovation in undergraduate medical education at US medical schools, the current structure and composition of clinical education in Internal Medicine (IM) is not clear. OBJECTIVE: To describe the current composition of undergraduate clinical education structure in IM. DESIGN: National annual Clerkship Directors in Internal Medicine (CDIM) cross-sectional survey. PARTICIPANTS: One hundred twenty-nine clerkship directors at all Liaison Committee on Medical Education accredited US medical schools with CDIM membership as of September 1, 2017. MAIN MEASURES: IM core clerkship and post-core clerkship structure descriptions, including duration, educational models, inpatient experiences, ambulatory experiences, and requirements. KEY RESULTS: The survey response rate was 83% (107/ 129). The majority of schools utilized one core IM clerkship model (67%) and continued to use a traditional block model for a majority of their students (84%). Overall 26% employed a Longitudinal Integrated Clerkship model and 14% employed a shared block model for some students. The mean inpatient duration was 7.0 ± 1.7 weeks (range 3-11 weeks) and 94% of clerkships stipulated that students spend some inpatient time on general medicine. IMspecific ambulatory experiences were not required for students in 65% of IM core clerkship models. Overall 75% of schools did not require an advanced IM clinical experience after the core clerkship; however, 66% of schools reported a high percentage of students (> 40%) electing to take an IM sub-internship. About half of schools (48%) did not require overnight call or night float during the clinical IM sub-internship. CONCLUSIONS: Although there are diverse core IM clerkship models, the majority of IM core clerkships are still traditional block models. The mean inpatient duration is 7 weeks and 65% of IM core clerkship models did not require IM-specific ambulatory education.