Dudley Pennell is Professor of Cardiology at National Heart and Lung Institute at Imperial College and an internationally renowned clinical cardiovascular researcher. He developed novel MRI-based methods for quantifying iron overload in thalassaemia patients that have made a major clinical impact, both reducing mortality in this condition and monitoring the effects of new therapies. He has probably contributed the most to establishing Cardiovascular Magnetic Resonance in clinical practice, phenotypically characterising dilated and hypertrophic cardiomyopathies and amyloid heart disease and demonstrating perfusion abnormalities in syndrome X. He is Director of the Royal Brompton Hospital NIHR Cardiovascular Biomedical Research Unit.