Purpose: Infusing continuity of care into medical student clerkships may accelerate professional development, preserve patient-centered attitudes, and improve primary care training. However, prospective, randomized studies of longitudinal curricula are lacking., Method: All entering Northwestern University Feinberg School of Medicine students in 2015 and 2016 were randomized to the Education Centered Medical Home (ECMH), a 4-year, team-based primary care clerkship; or a mentored individual preceptorship (IP) for 2 years followed by a traditional 4-week primary care clerkship. Students were surveyed 4 times (baseline, M1, M2, and M3 year [through 2018]); surveys included the Maslach Burnout Inventory (MBI); the Communication, Curriculum, and Culture (C3) survey assessing the hidden curriculum; and the Attitudes Toward Health Care Teams (ATHCT) scale. The authors analyzed results using an intent-to-treat approach., Results: Three hundred twenty-nine students were randomized; 316 (96%) participated in surveys. Seventy percent of all respondents would recommend the ECMH to incoming first-year students. ECMH students reported a more positive learning environment (overall quality, 4.4 ECMH vs 4.0 IP, P < .001), greater team-centered attitudes (ATHCT scale, 3.2 vs 3.0, P = .007), less exposure to negative aspects of the hidden curriculum (C3 scale, 4.6 vs 4.3, P < .001), and comparable medical knowledge acquisition. ECMH students established more continuity relationships with patients (2.2 vs 0.3, P < .001) and reported significantly higher professional efficacy (MBI-PE, 4.1 vs 3.9, P = .02)., Conclusions: In this randomized medical education trial, the ECMH provided superior primary care training across multiple outcomes compared with a traditional clerkship-based model, including improved professional efficacy.