Abstract: This study shows that the subjective sense of intoxication produced by ethyl alcohol exhibits classical sensory adaptation. The subjects reported a degree of intoxication that increased with the level of blood alcohol at the time of the report. However, a given level of blood alcohol produced less intoxication when it followed a high blood alcohol level than when it followed a low one. This effect of a prior level of blood alcohol on the effect of a present one implies that the mechanism that mediates alcohol intoxication adapts much as do exteroceptive sensory systems. Data on one chronic alcoholic suggest that alcohol abusers may adapt more rapidly than nonabusers.