A population sample of middle-aged women was randomly selected from the general population of women in Goteborg, Sweden. A representative subsample of women of ages 38, 46, 50, and 54 was selected for psychiatric examination (n=800). The psychiatric investigation consisted of a semistructured interview and the completions of a number of questionnaires. The aggression scale of the Cesarec-Marke Personality Schedule was used as an instrument for assessing aggression. The youngest group (age 38) was found to be the most aggressive, and there was no relationship between climacteric phase and high aggression. The reporting of parental hostility and poor emotional contact with the parents by aggressive subjects, especially with mothers, is in broad accordance with earlier studies of children and adolescents. The finding of a strong positive association between aggression and mental illness, especially depression, was not unexpected. Aggression was also associated with upward social mobility, reflecting the more intense striving for achievement in this group. Another expected finding was the higher number of aggressive women among the divorced and widowed. Tabular data and 18 references are provided.