The suicide rate in Norway was low and relatively stable during the first half of the 20th century. During the last 20 years it has increased dramatically. This increase has been most pronounced among young people of both sexes aged 15-19 years, and is the second highest in Europe. Females usually kill themselves by poisoning and men by shooting. The regional and temporal trends over the last 20 years show different patterns for the two sexes. The highest increase among men has occurred in the group aged 15-29 years in the northern part of the country, and for women in the group aged over 30 years in rural areas. The demonstrated increase does not seem to be due to more reliable registration of suicides. Attempts to explain the dramatic changes during the past decades have focused on social, demographic and economical changes in Norwegian society.