The increasing implementation of self-managing teams (smts) in service delivery suggests the importance of developing confidence beliefs about a team’s collective competence. This research examined causality in the linkage between employee confidence beliefs and performance for boundary-spanning smts delivering financial services. The authors distinguish between task-specific (i.e., team efficacy) and generalized (i.e., group potency) employee confidence, as well as between customer-based (i.e., customer-perceived service quality) and financial (i.e., service revenues) performance. They analyzed employee and customer survey data as well as financial performance data from 51 smts at two points in time using lagged analyses. The findings reveal divergent results for team efficacy and group potency, suggesting that team efficacy has reciprocal, causal relationships with service revenues and customer-perceived service quality. In contrast, group potency has no causal relationship with service revenues. Finally, customer-perceived service quality predicts group potency, whereas no evidence for the reverse effect is provided.