Teachers in the second stages of their careers--those with 4-10 years of experience--are often eager to vary their responsibilities, work collaboratively with peers, and influence teaching beyond their own classrooms. With many veteran teachers retiring, principals are apt to recruit these second-stage teachers to fill teacher leadership positions. In interviews with some second-stage teachers, the authors found that they had often struggled because their schools did not provide a professional framework or established a formal set of responsibilities to provide legitimacy to their leadership roles. The authors recommend that schools create stronger supports to help teacher leaders overcome the obstacles caused by the norms of school culture-teacher autonomy, egalitarianism, and deference to seniority.