Sexually transmitted infections are often acquired during travel. Infections are most often seen in young adults, travelling without a regular partner and among those who have higher numbers of partners while at home. Alcohol and recreational drug use may increase risk. The risks are highest from having unprotected sex with local partners in developing countries where the prevalence of infection can be many times higher than at home. The risks of acquiring HIV are highest in Africa, followed by South Asia. Special precautions are required by those going to work in health-care settings in high HIV prevalence countries. Travellers may benefit from advice about safer sex, condom use, emergency contraception and vaccination against hepatitis B. In special circumstances a starter pack for HIV post-exposure prophylaxis should be considered. Following return travellers should consider attending specialist services for a screen for sexually transmitted infections and HIV if they are concerned about exposure whilst travelling. A number of reports suggest that travel clinics need to pay more attention to the sexual health of travellers.