Our purpose was to investigate health care professionals' beliefs about effective teamwork in medical emergencies based on their experiences. We used framework analysis of interprofessional focus groups in four secondary and tertiary maternity units. The participants were randomly selected senior and junior doctors, senior and junior midwives, and health care assistants, in five groups of 5 to 7 participants each. We found that optimal teamwork was perceived to be dependent on good leadership and availability of experienced staff. The participants described a good leader as one who verbally declares being the leader, communicates clear objectives, and allocates critical tasks, including communication with patients or their family, to suitable individual members. We triangulated the results with evidence from simulation to identify convergent findings and issues requiring further research. The findings will inform the development of teaching programs for medical teams who manage emergencies to improve patient safety and experience.