This paper summarizes the research of the author into formative assessment. After an introduction, the second part introduces the idea of formative assessment and its historical context. Basic research investigating formative assessment in early years classrooms is then summarized and the conceptual framework of convergent and divergent introduced. The fourth part describes action research with primary school teachers to develop their practice using these concepts and an analytic framework of formative assessment processes. It also explains a more synthetic approach developed by the teacher researchers to accomplish formative assessment in practice. The fifth section shows how these ideas have been taken forward through research into formative assessment at university. Some of the outcomes of this research are then related speculatively to practice with younger children and readers are asked to appraise their relevance for a Polish (early years) setting. In particular the notion of learner identity is invoked as a way of making sense of formative assessment as a means of bridging the individual and social worlds of contemporary schooling and aspiration.