This investigation assesses the effects of leadership coaching on the knowledge, skills, and dispositions of urban public school administrators in P-12 underperforming schools. The study specifically examines leadership, management, and student achievement growth during the time of coaching. Utilizing a mixed-methods approach, three domains were assessed: (a) urban principals' perceptions about changes in their leadership behaviors, (b) student achievement growth on standardized tests during the time of coaching, and (c) participants' and coaches' perceptions of their experience in the program from interviews and coaches' logs. Results demonstrate significantly increased principal capacity in nine leadership responsibilities and positive student achievement gains after coaching the principals. This information will assist professional developers, university professors, and school personnel as they structure and implement programs to support urban school administrators.