Considering that traumatic injuries are the leading cause of death among young adults across the globe, emergency department care of polytrauma patients is a crucial aspect of optimized care and premature death prevention. Unfortunately, many studies have highlighted important gaps in collaboration among different trauma team professionals, posing a major quality-of-care challenge. Using the conceptual framework for interprofessional teamwork (IPT) of , the aim of this qualitative descriptive exploratory study was to better understand IPT from the perspective of health professionals in emergency department care of polytrauma patients, specifically by identifying factors that facilitate and impede IPT. Data were collected from a sample of 7 health professionals involved in the care of polytrauma patients through individual interviews and a focus group. In the second phase, 2 structured observations of polytrauma patient care were conducted. Following a thematic analysis, results revealed multiple factors affecting IPT, which can be divided into 5 broad categories: individual, relational, processual, organizational, and contextual. Individual factors, a category that is not part of the conceptual framework of , also emerged as playing a major part in IPT.