Two recent studies by Biancarosa et al. and by Saunders et al. have finally demonstrated that "job-embedded, sustained professional development" can significantly improve student achievement. But there's a catch. In both studies, effective professional development (PD) strategies were successful only under certain circumstances or only in some schools and classrooms. The determining factor was not the quality of the PD itself, but rather the conditions under which it was delivered. It turns out that job-embedded PD can be highly effective, but only when there is a sufficient infrastructure in place to support it. The TAP system, which is managed and supported by the National Institute for Excellence in Teaching (NIET), incorporates both of the strategies that the research studies have found to be potentially effective--"collaborative learning teams and instructional coaching." But TAP also takes the next critical step by helping schools create an infrastructure that supports high-quality PD and ensures that the activities ultimately deliver positive results, both for teachers and for their students. Building on recent research, this paper describes how the TAP system enables schools to support, oversee, and reinforce job-embedded PD so that teachers and students consistently benefit from it. This paper also describes how effective PD can be aligned with teacher evaluation systems to better ensure that teachers receive specific feedback to support improvements in their practice. (Contains 6 figures and 28 footnotes.)[This analysis was funded in part by a projected, multi-year federal Teacher Incentive Fund (TIF) grant awarded to the National Institute for Excellence in Teaching (NIET).]