Harry Bhadeshia is the Tata Steel Professor of Physical Metallurgy at the University of Cambridge and Professor of Computational Metallurgy at POSTECH. He graduated with a BSc from the City of London Polytechnic, followed by a PhD at the University of Cambridge. His research is concerned with the theory of solid-state transformations in metals, particularly multicomponent steels, with the goal of creating novel alloys and processes with the minimum use of resources. Harry Bhadeshia has carried out important work on the theory of solid state phase transformations, in particular the prediction and verification of microstructural development in multicomponent steels. He has made a major contribution to the understanding of the complex bainitic transformation by developing and using thermodynamic theory to show that different modes of transformation have measurable influences on the final microstructure. He is the author or coauthor of more than 500 research papers and six books on the subject. He is a Fellow of the Royal Society, Fellow of the Royal Academy of Engineering, the National Academy of Engineering (India) and the American Welding Society.