This study looks closely at the work of five teacher leaders within a grant designed to promote middle- and high school-level content area literacy teaching and learning. Drawing from research on teacher career cycles, teacher compensation, and distributed leadership, the five teacher leaders' motivations, meanings, and approaches to teacher leadership are explored. Data collection occurred over the 2006-2007 school year, and included both artifacts of leadership as well as teacher reflections on experiences. Findings include: (1) Teacher leaders were motivated both intrinsically and extrinsically, including by moral imperatives and monetary rewards, as well as professional and personal concerns; (2) The "teacher leader" designation meant surprisingly little; and (3) The teacher leaders had significant capacity to impact instructional change. Implications for both the development and utilization of teacher leaders as well as future teacher leader research are considered. (Contains 1 table.)