["Sociology of Health & Illness, Volume 43, Issue 1, Page 201-219, January 2021. ", "\nAbstract\nSelf‐harm in young people remains a significant concern. Studies of emergency departments have centred on negative professional attitudes. There has been limited interrogation and theorisation of what drives such attitudes, and the contexts that sustain them. Adopting a complex systems lens, this study aimed to explore how systems shape professional and patient interactions. It draws upon interviews with healthcare and affiliated professionals (n = 14) in a UK case study hospital, with primary focus on the emergency department. Data were analysed using a thematic approach and the principles of grounded theory. Four themes emerged, with the first three centralising how professionals’ practices operate within: (1) a framework of risk management; (2) expectations of progressing patients through the care pathway; and (3) a culture of specialist expertise, with resulting uncertainty about who is responsible for self‐harm. The fourth theme considers barriers to system change. A small number of participants described efforts to enact positive modifications to practices, but these were frustrated by entrenched system structures. The potential detrimental impacts for patient care and professional wellbeing are considered. Future practice needs systemic action to support professionals in treating patients experiencing self‐harm, while future research requires more ethnographic explorations of the complex system in situ.\n"]