Roberto Mayor is Professor of Developmental and Cellular Neurobiology at University College London. He is a world authority on development of the cephalic neural crest, an embryonic tissue that contributes to the formation of face and head. Cephalic neural crest cells are directly involved in craniofacial defects which account for one-third of all birth defects. His work has identified the causes of cleft lip and palate, demonstrating how genetic and environmental factors can combine to cause a birth defect. Professor Mayor is considered a leading figure in the emerging field of cell and tissue mechanics, and his work has wide implications in understanding cancer invasion and the origins of congenital craniofacial defects.