This article investigates when and how teams engage in team learning behaviours. More specifically, it looks into how different leadership styles facilitate team learning behaviour by influencing the social conditions that proceed them. 498 healthcare workers from 28 nursery teams filled out a questionnaire measuring the concepts leadership style, team learning behaviour, social cohesion and team psychological safety. Analysis was performed using structural equation modelling. The results of this cross-sectional study show that transformational leadership predicts team learning behaviour better then laissez-faire leadership, because transformational leadership is primarily related to team psychological safety and only secondarily to social cohesion while for laissez-faire leadership it works the other way around. Transformational leadership matters because it facilitates psychological safety in the team.