An analysis of the suicide and homicide rates of 48 countries is made to determine whether national suicide and homicide rates, on the one hand, and the relation between the rates, on the other, are related to economic development. The research hypothesis was supported in the finding that suicide rates tend to be high and homicide rates tend to be low in countries of high economic development and that suicide rates tend to be low and homicide rates tend to be high in countries of low economic development. The evidence indicates that economic developmentas measured by urbanization and industrialization—bears a fairly constant relation to the relative frequencies of suicide and homicide. It is thus concluded that suicide and homicide should be considered causally separate social phenomena.