Professor Mervyn Paterson is distinguished for his work on experimental geology and the deformation mechanisms of rocks and minerals. By training as an engineer, he has a flair for careful instrument design and built in Canberra some of the first and most successful and accurate high-temperature high-pressure apparatus for studying deformation of rocks and minerals. He has pioneered the experimental study of genesis of geological structures by using rocks themselves rather than model materials. His work on the development of kinking and folding in phyllite is now classical and his work on other problems such as annealing recrystallisation, deformation mechanisms, symmetry principles, and the mechanical properties of serpentinite are of fundamental importance for the geological sciences.