Martin Leach is Professor of Physics as Applied to Medicine and Director of the Cancer Research UK, Clinical Magnetic Resonance Research Group at the Institute of Cancer Research at the Royal Marsden Hospital. He has developed non-invasive measurement techniques, to address important clinical problems in clinical cancer diagnosis and management. In 1983, he installed the first clinical combined MRI and MRS instrument within a UK hospital and has used this to develop quantitative imaging techniques to measure perfusion and vascular permeability. This has allowed the first non-invasive study of VEGF-dependent prostate cancer response to treatment.