40 medical students were randomly assigned to an alcohol (1.32 ml per kilogram) or placebo group and were tested on two cognitive tests and a personality inventory. 10 alcohol subjects were tested on the Shipley-Hartford and Maudsley Personality Inventory on the ascending limb and 10 subjects were tested on the descending limb of the blood alcohol curve at a blood alcohol level of 0.08%. All 20 alcohol subjects were also tested on the Raven's Progressive Matrices on the descending limb. Placebo subjects were tested at comparable times as alcohol subjects. Performance was poorer on the Shipley for subjects tested on the ascending limb than for subjects tested at comparable blood alcohol levels on the descending limb. It was also found that more errors of omission were made on the Shipley in the ascending group than in the descending group. The nature of the alcohol impairment observed on the ascending limb seemed to be related to an expressive type deficit. Effects of alcohol on personality variables as measured by the Maudsley could not account for these differences. Subjects tested on the descending limb did not perform significantly differently from placebo subjects on either the Shipley or Matrices. Fast drinkers were found to have a slower elimination rate than slow drinkers, and elimination rate was positively related to cognitive performance. Methodological implications for future alcohol research are discussed.