He graduated MBChB from the University of Otago and PhD from the University of Auckland. Following paediatric training in Auckland Dr. Grant completed his postgraduate paediatric training in the United States, firstly as a paediatric resident at Duke University Medical Center, and then as a postdoctoral fellow at the Johns Hopkins University and Johns Hopkins Hospital. He holds qualifications as a paediatrician in Australasia (Fellow of the Royal Australasian College of Paediatrics) and the United States (Diplomat of the American Board of Paediatrics).