Book excerpt: Mathematics Teaching Today: Improving Practice, Improving Student Learning, Second Edition, updates the NCTM groundbreaking publication Professional Standards for Teaching Mathematics, first published in 1991. Like the original, this updated volume articulates a vision for effective mathematics teaching and describes the support systems that are required to achieve that vision. This book delineates Standards for various aspects of the teaching profession, including teachers' practise, professional supervision, collegial interaction and career-long professional growth. However, more than curriculum standards documents are needed to improve student learning and achievement. Teaching matters. Therefore, exploring what goes on in mathematics classrooms is essential to identifying issues and looking for opportunities for improvement. Principles and Standards for School Mathematics provides a framework for professional practise that supports the NCTM's vision of more and better mathematics for all children. This book expounds on that framework, explicating the roles of teachers, supervisors, teacher educators, mathematicians, professional developers, parents, politicians, community members and others in improving the teaching and learning of mathematics. The Standards offer a vision for high-quality mathematics teaching and support structures for teachers. What matters in the long run, however, is how classrooms across North America are transformed and how teaching practises evolve to address the mathematical learning needs of children.