Context: Transitions in medical education are dynamic, emotional and complex yet, unavoidable. Relationships matter, especially in times of transition. Using qualitative, social network research methods, we explored social relationships and social support as medical students transitioned from pre-clinical to clinical training. Methods: Eight medical students completed a social network map during a semi-structured interview within two weeks of beginning their clinical clerkships (T0) and then again four months later (T1). They indicated meaningful interactions that influenced their transition from pre-clinical to clinical training and discussed how these relationshipsimpacted their transition. We conducted mixed-methods analysis on this data. Results: At T0, eight participants described the influence of 128 people in their social support networks; this marginally increased to 134 at T1. People from within and beyond the clinical space made up participants’ social networks. As new relationships were created (eg with peers and doctors), old relationships were kept (eg with doctors and family) or dissolved over time (eg with near-peers and nurses). Participants deliberately created, kept or dissolved relationships over time dependent on whether they provided emotional support (eg they could trust them) or instrumental support (eg they provided academic guidance). Conclusions: This is the first social networks analysis paper to explore social networks in transitioning students in medicine. We found that undergraduate medical students’ social support networks were diverse, dynamic and deliberate as they transitioned to clerkships. Participants created and kept relationships with those they trusted and who provided emotional or instrumental support and dissolved relationships that did not provide these functions.