The field of travel medicine is concerned primarily with ways to maintain the health of international travelers. Remaining current in this area requires up-to-date knowledge of global infectious diseases, patterns of drug resistance, advances in preventive measures, and public health regulations pertaining to the crossing of international borders. This review of off-line commercial databases and Internet sources will assist infectious disease consultants in accessing current reliable travel health information. Of the North American pretravel off-line databases, TRAVAX (United States) and The Medical Letter are the most comprehensive, whereas the Global Infectious Disease and Epidemiology Network is extraordinary in its provision of global infectious disease epidemiology for posttravel assessment. A total of 65 Web sites are listed within 9 categories, covering such areas as authoritative government travel health recommendations, commercially-oriented sites, and travel medicine listserv discussion groups. Even among reputable Web sites, contradictory information may be found that demands careful consideration by the clinician and by the traveling public.