Healthcare teams are expected to deliver high quality and safe clinical care, a goal facilitated by an environment of psychological safety. We hypothesised that an individual’s personality would influence psychological safety, perceived stressors in the clinical environment and confer a suitability for different professional roles. Staff members were recruited from the Emergency or Critical Care Departments of one National Health Service Trust. Qualitative interviews explored participants’ experiences of personality, incorporating quantitative surveys to evaluate psychological safety and perceived stressors. The 16 Primary Factor Assessment provided a quantitative measure of personality. Participants demonstrated midrange scores for most personality traits, highlighting an ability to adapt to changing environments and requirements. There was a signal that different personality traits predominated between the two professional groups, and that certain traits were significantly associated with higher psychological safety and certain perceived stressors. Personality was described as having a strong influence on teamwork, the working environment and leadership ability. Our analysis highlights that personality can influence team dynamics and the suitability of individuals for certain clinical roles. Understanding the heterogeneity of personalities of team members and their likely responses to challenge may help leaders to support staff in times of challenge and improve team cohesiveness.