Since 9/11, some have voiced concern that terrorists or other criminals may exploit one of the U.S. visa programs -- the Visa Waiver Program (VWP) -- to enter the U.S. The program enables citizens of 28 participating countries to travel to the U.S. for tourism or business for 90 days or less without first obtaining a visa. This report reviews the VWP, including the process for assessing countries' eligibility to participate in the program. Determines the implications -- specifically those affecting national security, foreign relations, tourism, and State Dept. resources -- of eliminating the program. These VWP countries were visited: Belgium, Italy, Slovenia, Spain, Uruguay, and Argentina. Maps, charts and tables.