One of the most persistent features of the research environment in the UK over the last decades has been the Research Assessment Exercise (RAE); now more and more countries are following suit by developing their own systems for research quality assessment. However, in the field of education, one of the difficulties with this policy has been that a great deal of educational research characterises itself as either applied or practice-based. These are forms of research that have been notoriously difficult to accommodate within the RAE in all disciplines, not just in education. But what is applied and practice-based research in education? How can we define it and how can we assess its quality? The authors in this book come from diverse traditions within educational research, but through their papers each aims to contribute to the debate about what applied and practice-based research is and how we can understand, articulate and assess its quality. This book was first published as a special issue of Research Papers in Education: Policy and Practice.