Despite extensive theory and research on teams and leadership, few scholars have examined team leadership per se. To help fill this void, I examine a construct that intertwines leadership and teams: shared team leadership. Shared team leadership occurs when multiple individuals (not just the formal leader) exert downward, upward, and lateral influence (not just downward influence) on other team members in an effort to realize team goals. As shared team leadership is an emerging construct, I address several questions to understand (1) What is the relationship between shared and traditional conceptualizations of vertical team leadership? (2) How is shared team leadership different than potentially overlapping constructs? (3) What are the antecedents of shared team leadership? (4) How does shared team leadership relate to team processes, climate, and outcomes? and (5) How does shared team leadership relate to processes, climate, and outcomes over and above vertical team leadership as well as the potential overlapping constructs?

I examined these questions with a sample of 461 individuals in 39 fast-food restaurants using three different measurements of shared team leadership. Results illustrated both the promises and problems with the construct of shared team leadership. In particular, questions remained regarding several measurement issues of shared team leadership; there was a lack of between-group heterogeneity as well as convergent validity among the measures. However, the referent shift consensus measurement approach of shared team leadership was significantly and positively related to team functioning. Using this measurement strategy, shared team leadership was moderately related to the potential correlates of cooperation, helping, and climate for initiative. In addition, shared team leadership was related to the antecedent of team member ability, the team process of cohesion, climate for service, and the outcome of subjective performance assessments. Further, shared team leadership related to these potential consequences over and above vertical team leadership as well as the potential correlates in several cases. Overall, these results provide some support for shared team leadership, but also raise new questions about the construct.