In this study, we analysed the effects of team leadership style and magnitude of change on team behavioural interaction patterns (TBIPs) and performance in teams coping with unexpected task changes. Sixty-seven 3-person teams took part in a computer-based fire-fighting simulation task and were randomly assigned to one of the four conditions resulting from our 2 (leadership style: directive vs. empowering) × 2 (magnitude of change: high vs. low) longitudinal factorial design. Our results showed that empowering-led teams tend to display more TBIPs than directive-led teams. Through discontinuous random coefficient growth modelling, we observed that prechange TBIPs negatively affect teams' transition adaptation. However, postchange TBIPs were beneficial for teams' reacquisition adaptation. Implications for theory and practice are discussed.