The book Critical Mathematics Education provides Ole Skovsmose’s recent contribution to the further development of critical mathematics education. It gives examples of learning environments, which invite students to engage in investigative processes. It discusses how mathematics can be used for identifying cases of social injustice, and it shows how mathematics itself can become investigated critically. Critical Mathematics Education addresses issues with respect to racism, oppression, erosion of democracy, sustainability, formatting power of mathematics, and banality of mathematical expertise. It explores relationships between mathematics, ethics, crises, and critique. Ole Skovsmose has published what I might call his magnum opus, a 280-page synthesis and extension of his work simply called Critical Mathematics Education. In it he brings together his deep philosophical understanding and theorisation of mathematics itself, mathematics in society from a critical perspective, and mathematics in the teaching, learning and formation of students. For the mathematics education community, especially those concerned with social justice, philosophy, critical pedagogy and the nature of mathematics this is likely to be the publishing event of the year. In this book he offers something lacking in the literature, a philosophy of applied mathematics, as well as much more. Paul Ernest, Emeritus Professor, University of Exeter, UK