Background: Effective leadership is critical for the performance of health care teams and their intended outcomes for patient care. Given that team leadership is a modifiable and teachable skill, there is a need for a better understanding of this multidimensional behavior to inform future leadership training for health care action (HCA) teams. This systematized review identifies reported observed leadership behaviors in HCA teams, defined as interdisciplinary teams which complete vital tasks in complex, time-pressured, and dynamic situations. Methods: We searched CINAHL, MEDLINE, Scopus, PsycINFO, and Web of Science for peer-reviewed, English language articles using single and combinations of keywords including leadership, health care action team, and teamwork, individually. We included articles published until June 2021 without any specific beginning date. Results: From 242 records, 13 articles were included in the review. We categorized our findings of team leadership behaviors in HCAs based on an existing framework of three dimensions: transition processes, action processes, and interpersonal skills. The most-reported behaviors for transition processes were encouraging team members’ input, (re)assessing the team’s situation, and confirming team members’ understandings. The action processes dimension consisted of behaviors that included monitoring the progress of the patient, managing resources, asking for help when needed, coaching/supervising, and assisting team members as needed. Finally, closed-loop communication and facilitating team members speaking up behaviors were categorized as interpersonal skills. Conclusion: Although team leadership has been an area of focus in the field of health professions education, little attention has been paid to identifying the observable behaviors of effective team leaders in an HCA team. The study identified several new essential team leadership behaviors that had not been previously described, including seeking feedback, shared decision making, and aspects of interpersonal communication. The findings can inform educators in planning and implementing strategies to enhance HCA team leadership training, with the ultimate potential to improve health care.