The goal of this article is to clarify and unravel the complexity and challenges of improving teaching quality, based on measuring teaching quality and feeding back the results to teachers. We analyze different conceptualizations of teaching quality, and synthesize a framework for conceptualizing teaching quality in educational practice. We explain the pros and cons of four types of instruments for measuring teaching quality. Next, we scrutinize the requirements of effectively feeding back teaching quality data and the requirements for effective actions to improve teaching quality. We conclude with implications for improving the consequential validity of teaching quality measurements.