Laboratory manipulative studies confirm a correlation between the consumption of certain drugs and increased aggression. The potential mechanisms indicated by the resaerch are seen as causal only in the sense of how they can affect the likelihood of a specific behavior. The mechanism most easily defended is that pharmacological alteration in the threat system diminishes inhibitions toward aggression. The second proposed mechanism, psychomotor activation, explains the role of drugs that stimulate reward mechanisms and may increase aggression. There is also evidence to support the intuitive proposition that diminished cognitive functioning contributes to the disorganized and provocative behaviors of the intoxicated individual. 1 table, 4 figures, and 64 references