Professor Anne Watson taught mathematics in secondary schools for 13 years and since then has been a mathematics educator at the University of Oxford. She has always worked closely with teachers as well as researching mathematical learning, and has run numerous seminars and workshops throughout UK and abroad. Associate Professor Keith Jones taught mathematics in secondary schools for 12 years, during which time he was involved in curriculum development. Since then he has been a mathematics educator, first at the Institute of Education, London and now at the University of Southampton. He has led initial teacher courses in mathematics and his research involves working with teachers and students in schools and colleges. Professor Dave Pratt taught mathematics in secondary schools for 15 years and was involved in curriculum development, especially in relation to the use of technology in mathematics classrooms. Since then he has been a mathematics educator, first at the University of Warwick and then for the last three years at the Institute of Education, London. He has led PGCE courses for the initial teachers training in mathematics and his research involves working with young students.