Joseph Steenbrink (1947) studied mathematics at the University of Nijmegen, where he got his degree in 1969. He received his PhD at the University of Amsterdam in 1974, where Frans Oort was his supervisor. Subsequently he spent a year at the IHES at Bures sur Yvette, invited by Pierre Deligne. He was supported by an NWO stipend. He became assistant professor at the University of Amsterdam and full professor at Leiden University in 1978. Since 1988 he has the chair in geometry at the University of Nijmegen. He supervised nine PhD students, several of whom (Van Straten, Stevens, de Jong) now are full professor. His main research interest is algebraic geometry, where he has developed tools in mixed Hodge theory and applied these to singularity theory. He was one of the leaders of the successful NWO-projects in Singularity Theory and Arithmetic Algebraic Geometry. He was invited speaker at many international events, notably at the ICM 1990 in Kyoto. He has been Managing Editor of Compositio Mathematica from 1982 till 1993, and is a member of the Advisory Boards of North-Holland Mathematical Library and Epsilon Uitgaven. He was dean of the Faculty of Mathematics and Informatics during six years, and scientific director of the Mathematical Research Institute. His current research interests are: geometry of moduli spaces and of certain special threefolds. He published 50 research papers in refereed journals.