Jeff Johnson is an Assistant Professor of Computer Science at the University of San Francisco. After earning B.A. and Ph.D. degrees from Yale and Stanford Universities, he worked as a UI designer, implementer, manager, usability tester, and researcher at Cromemco, Xerox, US West, Hewlett-Packard, and Sun. He has taught at Stanford, Mills, and the University of Canterbury. He is a member of the ACM SIGCHI Academy and a recipient of SIGCHI’s Lifetime Achievement in Practice Award. He has authored articles on a variety of topics in HCI, as well as the books GUI Bloopers (1st and 2nd eds.), Web Bloopers, Designing with the Mind in Mind (1st and 2nd eds.), Conceptual Models: Core to Good Design (with Austin Henderson), and Designing User Interfaces for an Aging Population (with Kate Finn).