In order for teams to build a shared conception of their task, team learning is crucial. Benefits of intra-team learning have been demonstrated in numerous studies. However, teams do not operate in a vacuum, and interact with their environment to execute their tasks. Our knowledge of the added value of inter-team learning (team learning with external parties) is limited. Do both types of team learning compete over limited resources, or do they form a synergistic combination? We aim to shed light on the interplay between intra-and inter-team learning in relation to team performance, by including adaptive and transformative sub-processes of intra-team learning. A quantitative field study was conducted among 108 university teacher teams. The joint influence of intra-and inter-team learning as well as structural (task interdependence) and cultural (team efficacy) team characteristics on self-perceived and externally rated team performance were explored in a path model. The results showed that adaptive intra-team learning positively influenced self-perceived team performance, while transformative intra-team learning positively influenced externally rated team performance. Moreover, intra-team and inter-team learning were found to be both a constructive and a destructive combination. Adaptive intra-team learning combined with inter-team learning led to increased team performance, while transformative intra-team learning combined with inter-team learning hurt team performance. The findings demonstrate the importance of distinguishing between both the scope (intra-vs. inter-team) and the level (adaptive vs. transformative) of team learning in understanding team performance. Teamwork has become a self-evident aspect of work in organizations (Kozlowski and Ilgen 2006). By means of team learning, teams build a shared conception of their tasks and how to execute them, which is crucial for team performance: the degree to which teams reach or transcend their goals (Antoni and Hertel 2009; Van den Bossche et al. 2011). The first models on team learning mainly focussed on learning processes within the team (Edmondson 1999). While the importance of teams' external environment has been stressed in theoretical models (Decuyper et al. 2010;Kozlowski and Bell 2013), to date, empirical studies investigating both intra-team learning and inter-team learning simultaneously are scarce. As a result, insight in how inter-team learning and intrateam learning mutually influence team performance is still lacking, with some studies pointing to an added value of inter-team learning (Bresman 2010), while others demonstrate that inter-team learning forms an interference to team performance (Wong 2004). In the current study, we take an interactive approach and study how intra-team learning and inter-team learning may complement or compete over each other in their contribution to team performance.Team learning has been studied in a variety of professional contexts, for example among medical staff in healthcare (Timmermans et al. 2012), mil...