On analysing death registers of Finnish seafarers, 117 cases of suicide were found among active professional males in the years 1965-77. The suicide rate of the officers was similar to that of occupationally active males in the general population, while the suicide rate of the crew was 2 1/2 times higher (P less than 0.05). Many of the men who committed suicide had been at sea 5 to 10 years. Before their death they frequently changed ships.