Book excerpt: The book explains why and how schools and colleges in Wales have been inspected from 1839 to the present. It offers insights into the history of education and education policy making and describes how the ethos of the inspectorate changed over time. In the Victorian period, many inspectors condemned the use of Welsh in the school curriculum but later became active promoters of the teaching of the Welsh language, Welsh history and culture. It analyses the value and impact of inspection in the context of accountability and school improvement. This book critiques the debate about the future of inspection in Wales.