All 291 fatal accidents (510 persons on board, 318 drowned) in water traffic in Finland in 1986-1988 were investigated by specific teams. Only some data of this extensive investigation are presented in this study. Staggering and falling in boat because of drunkenness, falling over and sinking of boat were the main causes of getting into water of the people aboard. Only 3.5% of the drowned had used life jackets and 9.7% of them could not swim. The reduced ability to swim because of alcohol and the exhaustion were in about half of the drowned the actual cause and the cold water in one third the background factor for drowning. The results indicate that fatal accidents in water traffic are a major problem of males (95.9%) and give important information for countermeasures.