Volker Heine is a theoretical physicist who has made significant contributions to our understanding of materials at the atomic level. His computational models have had a substantial and wide-ranging impact on materials science, a broad scientific field with considerable practical interest. Volker’s interests have focused at times on metals and alloys, surfaces of solids, incommensurately modulated materials and minerals. He helped to develop and popularise the concept of the pseudopotential — the effective potential — in solid state physics, a highly effective method for reducing complex quantum potentials to more manageable approximations. He also helped to understand floppy atomistic vibrations in silicate framework structures, and their role in phase transitions and other properties. Since 1980, Volker has stimulated atomistic computer simulations using full quantum mechanical calculations and been a leader in building scientific cooperation across Europe through the Psi-k network. An Emeritus Professor at Clare College, University of Cambridge, Volker has received prestigious awards for his contributions to science. Foremost amongst these are the 1972 Maxwell Medal and the 2001 Born Medal of the Institute of Physics.