Professor Charles Brook MA, MD, FRCP, FRCPCH, was the founder and first director of the London Centre for Paediatric Endocrinology at Great Ormond Street and The Middlesex Hospitals. His professorial chair of Paediatric Endocrinology at University College London was the first academic appointment in this subject in UK. He is the author of more than 300 papers and the author or editor of 13 books. Now retired from the NHS and University, Professor Brook provides a consultation service offering opinion on all aspects of endocrine disease in children and adolescents.