Teams of professionals are deemed to be organizations' key drivers for solving complex problems. The team approach enables members to co-construct innovative solutions through engaging in team learning behaviors. However, such behaviors do not naturally occur. Team leadership behavior is often identified as a crucial factor for stimulating team learning, but specific empirical insights are lacking. The present study examined the effects of different leadership behaviors within 52 university teacher teams. Results of hierarchical regression analyses show that shared leadership was the most important factor for supporting team learning; more so than vertical team leadership. Specifically, members who encourage challenging the status quo predicted team learning, in contrast to focusing on structuring the task.