Derek Bell is Director of Graduate Studies and Research at Liverpool Hope University College and is Co-ordinator of the Nuffield Primary Science Project. He has over 20 years of experience in teaching and teacher education and has, for many years, run courses, carried out research, and written on subject/curriculum leadership in primary schools. Current research interests include subject leadership, teaching and learning in primary schools and children's understanding in science with particular reference to children with moderate learning difficulties. Ron Ritchie is Head of Department for Professional Development at Bath Spa University College. During his career he has taught in secondary and primary schools and been an advisory teacher in a large LEA. He has run inservice courses on subject co-ordination/leadership for many years. His research interests include professional learning and the roles and responsibilities of subject leaders. He has written widely in the field of primary education, including books on assessment, science and design and technology.