Tom Karygiannis is a principal investigator with the National Institute of Standards and Technology’s Computer Security Division. As a member of the Emerging Technologies Group, he conducts research in secure electronic commerce, network intrusion detection, personal digital assistant (PDA) security, and mobile agent security. Tom has over twelve years experience working with both private and public sector information technology organizations such as NASA’s Goddard Space Flight Center, the National Security Agency, the United States Agency for International Development, UNISYS, the Johns Hopkins University Applied Physics Lab, and the European Space Agency. Tom holds a Ph.D. in Computer Science from the George Washington University and a Master and Bachelor of Science degree in Electrical Engineering from Bucknell University.