Professor Alexander has made globally significant contributions to the science of gene transfer and translation through to therapeutic applications in genetic and acquired diseases of childhood. He has played a pioneering role in the establishment of the gene therapy field in Australia, providing leadership in the formation of a specialist society, contributions to regulatory oversight, the introduction of gene transfer technologies to the Australian biomedical community, and through undertaking ground-breaking clinical trials. He has also been highly influential in championing the importance of basic science in paediatric medicine and in the development of an integrated approach to rare disease research.