Although it is often mentioned in articles about learning and teaching, surpris- ingly few recent studies have systematically investigated the meaning of feedback in classrooms. In this article, we begin with a conceptual analysis of the meaning of feedback and a synthesis of the evidence related to the power of feedback to improve teaching and learning. We then propose a model of feedback that is used to identify the circumstances under which feedback has the greatest impact. Specifically, the research evidence related to the different types of feedback and their effectiveness in terms of promoting student learning are discussed, the dif- ferent ways students deal with feedback are described, and the relationship between assessment and feedback is provided. Finally, the model, together with the evidence underpinning it, is used to show how feedback can be used to enhance classroom learning and teaching.