Team leadership research has largely relied on traditional dyadic models (i.e., those capturing one-on-one relationships between a leader and follower) to explain team-level phenomena. Despite recent advancements, much of this research falls short of addressing the complexity inherent to teams. One promising alternative to the traditional perspectives, functional leadership theory, moves beyond the constraints of dyadic models and instead advances a needs-based approach for understanding team leadership (i.e., effective leaders are those that meet any and all team needs). Although intuitive, the ambiguous nature of simply meeting team needs does not provide sufficient specificity as to how exactly leaders meet team needs. In an effort to address this issue, I introduce a multi-dimensional construct, called leader focus, to explain how leaders meet team needs by focusing their efforts on teamwork or taskwork (i.e., person-task focus) as well as different relational entities in the team (i.e., entity focus). In total, I propose six unique foci of team leadership: individual task-focus, team task-focus, subgroup task-focus, individual person-focus, team person-focus, and subgroup person-focus. Next, using social interdependence theory, I hypothesize that individual-focused leadership is most effective when task interdependence is low, whereas team- and subgroup-focused leadership are most effective when task interdependence is high. Further, person-focused leadership is hypothesized to influence team effectiveness by way of interpersonal processes; task-focused leadership is argued to influence team effectiveness via task-related processes. In a sample of 89 firefighting crews, partial support is found for the multi-foci model of team leadership. Team task-focused leadership influences team task performance indirectly through task processes; team person-focused and subgroup person-focused leadership influence team helping behaviors through interpersonal processes. Moreover, the relationship between individual task-focused and subgroup task-focused leadership on team processes is contingent on task interdependence. Theoretical and practical implications are discussed.