In the past decade, interest in coaching has exploded in the USA. Coaching is recognised as one way to significantly improve teaching practices and many states, districts, and schools are hiring coaches to deliver professional learning in their schools. However, in their enthusiastic efforts to obtain professional development that makes a difference, some leaders have hired coaches without considering the principles, actions, and contextual factors that have been found to increase coaching success. This chapter provides an overview of each of these topics, with a major focus on instructional coaching (Knight, 2007). At the same time, issues that are relevant to any coaching designed to improve the way teachers teach and the way students learn is considered.