Dr Sara Mole read Natural Sciences at Cambridge before a PhD in Biochemistry at Imperial College of Science and Technology London. She then undertook postdoctoral research in molecular biology then molecular genetics, always with a link to disease. She has focused on Batten disease at University College London since 1992, contributing to the identification of the first genes and then their functional biology. In 1998 she launched the Mutation Database, which was later expanded into the web site NCL Resource to additionally provide a global gateway for Batten disease. In 1998 she co-edited a monograph on Batten disease that is the forerunner to this much expanded edition. ; Dr Ruth Williams studied medicine at The University of Nottingham, graduating in 1985. She trained in Paediatrics and in Paediatric Neurology before taking up her current post as a Consultant Paediatric Neurologist at the Evelina Children's Hospital in 2003. As part of her training she undertook a period of research into the genetic basis of the NCLs and obtained her doctorate in 1996. Her special interests include the diagnosis and management of childhood epilepsies and the NCLs. ; Prof. Hans H. Goebel is a neuropathologist who received his specialty education in neuropathology at New York University and in the Indiana University Medical Center in Indianapolis/USA. There he applied the technique of electron microscopy to innumerable biopsied and autopsied human tissues affected by neuronal ceroid lipofuscinoses (NCL) and other lysosomal and neurodegenerative diseases. He has written numerous articles and book chapters on the neuropathology and especially the ultrastructure of the NCLs. In 1999 he edited a monograph on NCL which grew out of a Concerted Action of the European Union concerning the NCL.