In a questionnaire survey on sexual behaviour, a random sample of 10,000 Norwegians aged 18 through 60 were asked about use of condoms during their last intercourse. The response rate was 62.7%. Except as regards level of education, the response group was fairly representative of the population with respect to socio-demographic variables. About 12% reported use of condom. Among subjects who reported extra-marital partners, about 7% used condoms (both with their permanent and their extra-marital partner), whereas about 12% of subjects who did not have extramarital sex used condoms. 15% of the single persons reported use of condom. Apparently, the use of condoms is not related to sexual behaviour correlated with risk of HIV-infection, such as the number of partners and knowledge about the partner. Neither is perceived risk, as measured by HIV-testing behaviour, related to the use of condoms.