The seasonal variation in suicides in Finland during the period 1961-1976 was examined using individual records from 16,312 death certificates and time-series analysis. De-trended figures show that suicides are usually concentrated in early summer but a secondary rise in the late part of the year is noted, particularly in females, among those aged 15-24 years and in the highest and lowest (i.e. unknown) social classes. In modern occupations (technical, administrative, clerical, sales and service work) suicides usually occur in late autumn. It is suggested that the original seasonal peak in suicides lies in spring-summer, while the autumn peak is of later origin and typical of those living in a man-made environment.