Alan MacEachren is a Professor of Geography & Information Science and Technology at Penn State University where he directs the GeoVISTA Center. His research interests include geovisualization, visual analytics, spatial cognition, human-computer interaction, exploratory data analysis, and geosemantics. He was founding Chair of the International Cartographic Association Commission on Visualization, one of the authors of IT Roadmap to a Geospatial Future (a National Research Council report) and of Illuminating the Path: The R&D Agenda for Visual Analytics, Co-Editor of Exploring Geovisualization, and author of How Maps Work: Representation, Visualization, and Design. He is currently an Associate Editor for both Information Visualization and IEEE Transactions on Visualization & Computer Graphics.http://www.geovista.psu.edu/members/maceachren/index.html.