Christodoulou is one of the most remarkable writers in education the UK has seen in decades, because she takes a subject as potentially opaque and esoteric as assessment, and unpacks it in an intelligible, vital way that neither patronises the novice or offends the expert. Her first book, 'Seven Myths', is one of the few texts that every new teacher should read. Her second book is, rather amazingly, another. It should be read deeply, broadly, everywhere that children are taught and assessments are used. Tom Bennett, chair of the DfE Behaviour Management Group and founder of researchED Daisy is one of the leading thinkers on assessment in the UK and this book is essential reading for everyone who works in education. It shows that flaws in assessment are the cause of so many issues in our education system and gives us a clear path to fixing those flaws. Sam Freedman, Executive Director of Programmes at Teach First and trustee of the Teacher Development Trust