Travel medicine is an interdisciplinary specialty concerned not only with prevention of infectious diseases during travel but also with personal safety and prevention of environmental risk. Travel medicine focuses primarily on pre-travel preventive care of persons and less on the diagnosis and treatment of illness acquired in the tropics. To provide optimal pre-travel preventive service, it is needed for the travel health provider to be aware of the epidemiology of the many travel-related health risks. But still the knowledge of the precise risks for a specific disease in a specific location has proved elusive and the application of evidence-based standards to travel medicine is a challenge. The GeoSentinel, a worldwide communication and data collection network for the surveillance of travel related morbidity and mortality was initiated in 1995, and provides various epidemiologic features needed in pre-travel risk assessment. The three essential elements of pre-travel health service are risk assessment, risk management and risk communication. The risk assessment includes both assessing the health problem of the traveler and the risk of travel itself. Hence the health risks of a specific destination is changeable over time, they should be evaluated with last informations provided from World Health Organizations or other professional institutes for travel health. The essential services for risk management include vacccination, chemoprophylaxis (e.g.,malaria), and education the risk and prevention of insetborne, foodborne, animal-related diseases, behavioral safety, and any other known risks. The of travel-related diseases of Korean travelers are not quite clear yet. It is recommended that the travel-related disease surveillance system for Korean travelers should be improved so as to provide evidences needed to assess the risks and to prescribe preventive services.