Over 70% of the adult population of five rural communities in Northern Norway participated in a three-part epidemiological study that included identical questions on mental health. Data were collected in 1987/88, 1990 and 1993. Both repeated cross-sectional analyses and individual growth curve analyses on the 2,486 individuals who participated in either two or three surveys were carried out in order to reveal the changes in mental health over time. The proportion of the population using sleeping pills or psychotropic drugs decreased significantly as time progressed. There were also a significant decrease in the proportion of people who reported being depressed or dissatisfied with life, or who had insomnia or problems in coping. A similar improvement in mental health was noted for both sexes and it remained statistically significant even after adjusting for age and level of education. There was no decrease in the proportion of individuals who reported loneliness. The time effect remained significant, even after adjusting for multiple factors in the growth curve analyses. Improvement in mental health has occurred despite the crisis in the region's fishing industry.