David O'Sullivan is an Associate Professor of Geography at the University of California, Berkeley, having recently moved from the University of Auckland. Prior to those appointments, he was an Assistant Professor in the GeoVISTA Center at Penn State University, and he completed his PhD at the Centre for Advanced Spatial Analysis, University College, London. He works in the areas of spatial analysis and modeling, with a particular focus on the implications of geospatial technologies, computation, and especially, the complexity sciences, for how we represent the world, and then use those representations to do geography. He has recently published a new book, Spatial Simulation: Exploring Pattern and Process, with his former University of Auckland colleague, George Perry. He is also the author, with David Unwin, of a well known text on spatial analysis, Geographic Information Analysis, currently in its second edition