Of 9,026 males aged 50-69 years, 1,494 were randomly selected and invited to participate in a programme including two screenings for carcinoma of the prostate by digital rectal examination performed in 1987 and 1990. The remaining 7,532 served as a control group. Of the selected persons, 78% accepted the invitation to the first screening round and 70% to the second one. Carcinoma of the prostate was suspected in 45 of 1,163 men examined at the first screening round and in 42 of 953 at the second round. Carcinoma was confirmed by fine-needle aspiration biopsy in 13 cases from the first and in 7 from the second round. In the study group, 17.4 carcinomas were diagnosed per 1,000 men and in the control group 8.6 per 1,000 men. The screening cost was 1,640 pounds per detected cancer and 2,343 pounds per detected and potentially cured cancer. Screening for carcinoma of the prostate by digital rectal examination can be organised with a high population acceptance, and at a reasonable cost. The impact of screening on mortality in prostatic cancer remains uncertain.