Improving educator effectiveness and school functioning requires continuous attention to practice selection, implementation fidelity, and progress monitoring, especially in the context of systemic school reform efforts. As such, supporting professional development must be targeted, comprehensive, efficient, and relevant. In particular, coaching must be established to bridge the implementation gap from knowing-to-doing. To increase the precision with which we develop and use coaching supports, we describe how (a) coaching is conceptualized, described, and operationalized within a multi-tiered system of support (MTSS) framework using a behavioral approach; (b) professional development activities are considered from a teaching and phases of learning perspective; and (c) critical coaching components are implemented from within a multi-tiered support systems framework. Existing and future research about effective coaching is also considered.