Travelling to tropical and subtropical destinations is common among European citizens. Many of them consult their general practitioners (GPs) for pre-travel advice. Little is known about the knowledge, the sources of information and the needs of physicians. One hundred and fifty Swiss and 150 German GPs giving travel advice were interviewed using pretested telephone interviews and questionnaires to assess their knowledge about travel advice to be given for 2 frequent holiday destinations (Kenya and Thailand), and to ask which information sources were available to them. Ninety-six per cent and 89%, respectively, of GPs in 2 neighbouring areas of Switzerland and Germany gave travel advice to their clients. In telephone interviews, standard recommendations on malaria medication, as approved by the national travel advice committees, were stated by 45 and 25% of Swiss GPs, and 22 and 9% of German GPs for Kenya and Thailand. The figures for correct advice on vaccination requirements were 23 and 47% for the Swiss GPs, and 2 and 25% for the German GPs. Half of the GPs wanted to consult their documents before giving advice. The main source of information used by Swiss GPs was the monthly updated Bulletin of the Federal Office of Public Health (BFOPH). A variety of different sources was recorded among German practitioners. Regular, concise information on travel advice tops the list of requested information material in both countries. The extent of correct pre-travel advice is unsatisfactory in both study groups. Use of standardized, regularly updated and readily available sources of information on travel advice for the GP could avoid uncertainties of both the provider and the recipient of advice.