In this chapter I explore a proposition made many years ago in a lecture given by Professor Marten Shipman to the Primary Education Study Group (Cullingford, 1997); he claimed that ‘there is a close and necessary relationship between what we choose to assess and what we value most in the education of our children’. The exploration opens with a story about a six-year-old child whom I knew well; his story introduces the theme of choice that runs through the rest of the chapter. My argument is that in the effective practice of assessment, educators make principled and value-driven choices about children, about learning and achievements. As a result they are able to make well-judged choices about the methods, purposes and outcomes of assessment.