Hans Meinhardt works at the Max Planck Institute for Developmental Biology in Tübingen, Germany; since 2003 as Emeritus. He studied physics in Cologne and Heidelberg. After his PhD he worked for two years at CERN, the European High Energy Laboratory near Geneva, where he learned to use computers for modeling complex systems. Since 1969 at the Max-Planck-Institute, his interest moved towards biological problems. In part together with Alfred Gierer he developed molecular feasible models for essential steps in the development of higher organisms. Several of these models have now found direct support in molecular and genetic research.