Poisoning mortality rates have increased considerably in Denmark and Sweden, slightly in Norway, and remained essentially the same in Finland, during the period 1961 to 1973. In the present study, fatal poisoning included cases of intoxication by solid or liquid substances classified as suicidal, accidental (alcohol poisonings excepted) or of undetermined intent. From 1961 to 1973 poisoning mortality rates increased in Sweden by about 200%, in Denmark by about 100%, and in Norway by about 50%. In males, the age-standardized mortality rates were: in Denmark and Sweden, about 130; in Finland, about 70, and in Norway, about 30 cases per one million of population in1972. The corresponding figures for females were 125, 75, 40 and 20. Despite this overall rise, rates of suicidal poisoning mortality and mortality from accidental poisoning have decreased in Sweden since 1969. From this year onwards, the classification category "undetermined poisoning" has been used and the decreases in other categories are compensated by an increase in this group. On the basis of the scanty data available, the substances most frequently responsible for fatal poisoning are drugs (in particular barbiturates), other soporifics, and tranquilizers. There is some evidence that poisoning mortality is correlated with the prevalence of drug use and could consequently be reduced by drug control.