Dietrich Welte is an internationally known petroleum geochemist and professor. His work in industry includes time spent with Royal Dutch Shell and with the Chevron Lab in California. He was appointed to professorships in geochemistry with the University of Wurzberg and the University of Gottingen. He has held the RWTH Archen University Oil and Carbonology Chair. Dietrich’s work with Bernard Tissot in the 1970s led to their publishing in 1978 the globally influential volume, Petroleum Formation and Occurrence, which became a widely used textbook. Developing his interest in petroleum basin evolution and modeling, Dietrich founded Integrated Exploration Systems (IES). With Brian Horsfield and Donald Baker, Dietrich edited the important book Petroleum and Basin Evolution: Insights from Petroleum Geochemistry, Geology and Basin Modeling. Dietrich’s body of work was honored by the AAPG with the Sidney Powers Memorial Award.