We examined the impact of a team leader coaching intervention on episodic team processes (transition, action, interpersonal) and subsequent team performance outcomes within a surgical context. Specifically, we tested whether coaching team leaders (i.e., surgeons) on promoting effective teamwork facilitates team processes and two important outcomes-delays and distractions. Team processes were indexed using detailed observational protocols by subject-matter experts before and during surgeries. We employed an interrupted time series design whereby half of our participants received coaching midway through the longitudinal period and the remaining served as a quasi-control group. Team processes and outcomes were collected from multiple surgeries, per surgeon, both before and after the coaching intervention (N = 223 surgeries total). Results from a multilevel mixed-model (treatment vs. control, over time) structural equation model suggest that teams where the surgeon (team leader) received the coaching intervention exhibited higher-quality team transition processes. Transition processes related positively to subsequent action and interpersonal processes, which in turn yielded improvements in two different surgical team performance outcomes. Theoretical and applied implications are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).