Purpose: Drawing on social capital theory and self-identification theory, this study aims to examine the associations of two indicators of social capital, personal networks and deep-level similarity, with team capability measures of team efficacy and team potency. The central focus of the study is to be the hypothesized mediating role of team learning behaviors. Design/methodology/approach: Hypotheses were tested using questionnaire data obtained from 221 teachers working in 33 teams and data were analyzed using multilevel analyses. Findings: Consistent with the hypotheses, the results supported the contention that team learning behaviors mediate the relationship between different types of social capital and team efficacy and team potency. Specifically, it was found that, in highly (deep-level) similar teams, the level of team learning behaviors is higher than in diverse teams, and this is hardly dependent on the extent of social capital based on personal networks. For diverse teams (i.e. teams scoring low on deep-level similarity) more social capital based on personal networks translates into more team learning behaviors. Finally, it was found that team learning behaviors mediate the influence of social capital on team efficacy and team potency. Research limitations/implications: The paper's findings suggest that it is important for managers not to focus exclusively on surface level characteristics but instead to attempt to facilitate the development of deep-level similarity. Organizations can also encourage group social capital by allowing teams to develop a shared history, rather than change membership frequently, and by increasing contact among team members. Originality/value: The paper examined exchange and identification processes that are important in generating resources to increase the development of team learning behaviors, thereby emphasizing the role of the interpersonal context for understanding how interaction processes between team members shape team learning behaviors and subsequently lead to more team efficacy and team potency. (Contains 2 tables and 1 figure.)