In most developed countries, the pursuit of reliable and valid means of assessing people's learning generates high volumes of published discourse and, not infrequently, dissent; the documentation on the various assessment policies, practices and theories could conceivably fill whole libraries. Some of the discourse and much of the dissent relate to whether the use to which assessment is put is valid or useful to the learners themselves or to other audiences. The pursuit of the authors is somewhat different. The authors would argue that learning should take centre stage and address the role that assessment should play in this. Assessment is the focus but learning is the goal. A theme that plays out through every successful instance of assessment for learning is the motivation to learn that it generates among students. It is arguably uncontentious that students are motivated to learn if they participate in developing their learning activities, if they know how their work will be assessed and if they are involved in assessing it with their peers. Perhaps it is also unnecessary to point out that students' motivation is enhanced by the ability to engage readily with their teacher, to receive feedback that supports the next steps in their learning or by being involved in drawing up the criteria against which they will be assessed. Following Contributors' Details, and "Assessment and Learning: An Introduction" (John Gardner), this book is divided into four parts. Part I, "Practice", contains the first two chapters: (1) Assessment for Learning in the Classroom (Paul Black and Dylan Wiliam); and (2) Professional Learning as a Condition for Assessment for Learning (Mary James and David Pedder). Part II, "Theory", presents the second group of chapters: (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 Wiliam). Part III, "Formative and Summative Issues", contains the next three chapters: (6) On the Relationship between Assessment for Formative and Summative Purposes (Wynne Harlen); (7) The Reliability of Assessments (Paul Black and Dylan Wiliam); and (8) The Validity of Formative Assessment (Gordon Stobart). Part IV, "Policy" contains the final group of chapters: (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 Wiliam); and (11) Policy and Practice in Assessment for Learning: the Experience of Selected OECD Countries (Judy Sebba). The book concludes with, "Assessment for Learning: A Compelling Conceptualization" (John Gardner), References, Author Index, and Subject Index. [This book is published by Paul Chapman Publishing.]