This book provides a comprehensive overview of assessment used to support learning, and it makes this area accessible and understandable for a wise range of users. This unique text is a major source of practice-based theory on assessment for learning, a formative assessment to support individual development and motivate learners. Key areas covered in the book include the practice of learning for assessment in the classroom, developing motivation for learning, professional learning and assessment for learning, and assessment and theories of learning. The book's authors are all part of the internationally known Assessment Reform Group (ARG), which is influential in the field of assessment and inclusion policy. The group carries out research in order to reach policymakers in government, and also works closely with teachers and local authority staff. Following an introduction by the editor, the book divides into four parts and 12 sections. Part I, Practice, contains: (1) Assessment for Learning in the Classroom (Paul Black and Dylan William); and (2) Professional Learning as a Condition for Assessment for Learning (Mary James and David Pedder). Part II, Theory, contains: (3) Assessment, Teaching and Theories of Learning (Mary James); (4) The Role of Assessment in Developing Motivation for Learning (Wynne Harlen); and (5) Developing a Theory of Formative Assessment (Paul Black and Dylan William). Part III, Formative and Summative Issues, contains: (6) On the Relationship between Assessment for Formative and Summative Purposes (Wynne Harlen); (7) The Reliability of Assessments (Paul Black and Dylan William); and (8) The Validity of Formative Assessments (Gordon Stobart). Part IV, Policy, contains: (9) Constructing Assessment for Learning in the UK Policy Environment (Richard Daugherty and Kathryn Ecclestone); (10) Assessment for Learning: Why No Profile in US Policy? (Dylan William); (11) Policy and Practice in Assessment for Learning: The Experience of Selected OECD Countries (Judy Sebba); and (12) Assessment for Learning: A Compelling Conceptualization (John Gardner).