Team reflexivity (TR)–defined as a team's conscious reflection on their objectives, strategies, and processes—is an important team process that fosters adaptation and information processing. However, traditional conceptualizations frame TR as a process that occurs in periods of downtime to reflect on past, terminated performance, largely ignoring reflective team processes occurring during intense performance events of action teams. To address this gap, we conceptualize TR as a team process that occurs not only during periods of downtime after the action but also during performance events as brief TR moments. We elaborate on the concept of in-action TR and explore it by delineating its relationship to task type and timing during a performance event. Further, we test a team level contingency model of in-action TR, namely, team size and performance. Using behavior observation, we test our hypothesis with 70 medical teams responding to simulated in-hospital emergencies. Task type is related to in-action TR and reflection tends to increase as action progresses. Further, in-action TR is related to team performance and is especially important for larger teams. Our study is the first to investigate in-action TR and provides theoretical and practical implications on how in-action TR operates in extreme action teams.