This paper rests on two propositions: that inservice training must radically change to result in the transfer of training to classroom practice, and that inservice training must be embedded in coherent school improvement programs in order for change to be sustained. Accordingly, the first section reviews three recent research studies designed to build understanding of the problems of transfer, increase rates of transer of training, and determine the extent of attrition over time when training was boosted by the coaching of teaching and peer coaching. The second section discusses the critical importance of staff development in school improvement, arguing that, on the basis of the research, the provision of coaching following initial training--even very strong training--will be necessary if new behaviors are to be integrated into classroom practice. The design and implementation of powerful training systems will require the full support of leadership at both the district and building levels. Administrators will have to examine priorities for staff development and the allocation of funds. Further, the organization of peer coaching systems will need to be cooperatively arranged between district administrators and school sites. Principals will be in a position to assist with more than just the logistics of peer coaching--they will be able to facilitate the implementation of such systems through establishing new norms that reward collegial planning, public teaching, constructive feedback and experimentation and through collaborative problem solving with their teachers. (TE)