I attended UCLA and University of Cambridge for my MD and PhD degrees and then trained as a pediatrician and neonatologist at Boston Children’s Hospital. I was a postdoctoral fellow in Andy McMahon’s lab at Harvard University. As a physician-scientist, I have investigated extensions of neuroscience that can impact our understanding of human neurological diseases, particularly cerebral palsy, multiple sclerosis and brain cancers. For over 15 years we have investigated the developmental genetics of the glial lineages of the brain and novel functions for astrocytes and oligodendrocytes. I helped establish the first “Neuro-NICU” in the USA at UCSF. This inter-disciplinary unit, focused on newborn neurological injuries, has improved standards of care and has facilitated basic and clinical research. I directed a first-in-man Phase I study of neural stem cell transplant into the human brain for leukodystrophy as an approach for demyelinating disorders. As a HHMI Investigator, I established a basic program of research in human neonatal brain development that has attracted support of an NINDS PO1. In 2016 I joined University of Cambridge as Head of Department of Paediatrics, where we investigate application of whole genome sequencing in care of intensively ill children supported by the UK National Institute for Health Research. I am a Wellcome Trust Senior Investigator with a laboratory in the Wellcome-MRC Cambridge Stem Cell Institute. I am an Adjunct Professor of Pediatrics and Neurosurgery and have a lab at UCSF in the Eli and Edyth Broad Institute for Stem Cell Research and Regenerative Medicine. I was appointed to the National Advisory Council Child Health and Development, National Institutes of Health in 2020, and elected as a Fellow of the Royal Society in 2021.