Findings of a study that examined the extent to which transformational forms of leadership contribute to teacher commitment are presented in this paper. Teachers' commitment to change is expressed as a function of personal goals, two types of personal agency beliefs, and emotional arousal processes. Alterable variables giving rise to commitment are conceptualized as a set of eight in-school and out-of-school conditions as well as seven dimensions of transformational leadership practices. Data were derived from a survey of 168 teachers (of whom 91 percent were involved in implementing school improvement efforts) in 9 secondary schools in a large urban school district. Path analysis was used to generate three models. Findings indicate that each class of variables appeared to exercise a significant influence on teachers' commitment. Vision-creating and goal consensus-building practices of school leaders had especially strong effects on motivational conditions associated with teachers' personal goals, which, in turn, were significantly related to teachers' context and capacity beliefs. In summary, the dimensions of leadership practice that contributed most to teachers' commitment to change were those that helped to give direction, purpose, and meaning to teachers' work. Four figures and four tables are included. (Contains 68 references.) (LMI)