Aim The aim was to determine whether there are relationships among transformational leadership, safe team climate, knowledge sharing and reflection, and team performance in nursing and social work teams. Background Based on organisational learning theory, we hypothesized that transformational leadership could create a safe team climate that fosters knowledge sharing and reflection in teams and thus influences the performance of teams. Methods We conducted a cross-sectional study using questionnaires and validated scales to measure transformational leadership, safe team climate, knowledge sharing and reflection, and performance. The sample consisted of 32 teams (N = 32 teams,n = 183 team members). Results We conducted structural equation modelling. The results indicate that reflection positively relates with team performance, transformational leadership has a direct positive relationship with safe team climate, and safe team climate has positive relationships with knowledge sharing and reflection. Conclusion Our findings regarding transformational leadership's positive influence on teams in nursing and social work fill an important gap in the literature. The study's limitations are the use of self-reports and a small sample size. Implications for nursing management Our results indicate that transformational leadership can foster a safe climate in work teams and hereby team learning and performance.