Suicides and suicide attempts in cancer patients were analysed by following all patients treated for cancer in Stockholm County from 1975 to 1985. Among 59,845 patients we identified 144 suicides and 196 suicide attempts during the follow-up, which represents a more than two-fold excess mortality from suicide and a moderately increased rate of suicide attempts. Although the absolute number of deaths from suicide in cancer patients is low, the increased risk highlights the problems of coping with severe illness and the need for psychological and social support in cancer care.