Effective teamwork in interprofessional healthcare teams requires expert performance by individuals in clearly defined roles. This focus on role clarity and role performance provides the basis of the ‘pit crew’ approach, now commonly utilized in resuscitation teams with demonstrated benefits in patient care. Maternity teams responding to emergencies may benefit from a similar approach to teamwork; however, little attention has been paid to team member roles within the maternity emergency context. In this qualitative case study of maternity teams responding to two simulated maternity emergencies in the context of a teamwork training course, we aimed to describe team member performance in roles and explore clinician perceptions of role allocation and performance within the team. Video analysis of role performance demonstrated team members performed actively and passively in multiple roles throughout the scenario, with some improvement in role consistency between Case 1 and Case 2. Workload distribution was uneven, with some clinicians performing tasks across several roles concurrently, while others did not appear to take on any role. Thematic analysis of debriefing conversations and post-scenario interviews and focus groups revealed four themes. Three themes related to the process of team member allocation to roles with participants describing the need to firstly gain an understanding of the situation, have knowledge of clinical requirements and priorities and consider their suitability for role in the clinical case. The fourth theme related to participants shift in conceptual understanding of how to work in roles facilitated by the simulations and debriefings. This study provides a preliminary understanding of how team members allocate roles in ad hoc maternity teams and supports the use of simulation-based training to improve role-based teamwork. Further research is recommended to enhance our understanding of the impact of role-based teamwork in maternity emergencies, and how simulation and debriefing can most effectively improve this important domain of teamwork.