This report summarizes experimental results obtained in the elevation of the effect of alcohol alone and in combination with other drugs as influenced by decreased environmental temperatures. The acute toxicity of ethyl alcohol was doubled by 24 hours exposure to 0-5° C, immediately prior to administration of the test. Cold exposure of 2, 24 or 168 hours did not materially affect the height of the blood alcohol level, nor was there any difference in the time required to reach maximum blood concentrations in animals given single doses. There were no significant differences in the alcohol blood/brain and brain/breath ratios resulting from short or prolonged exposures to cold. Motor coordination, as measured by ability to maintain equilibrium, deteriorated significantly in animals exposed to cold for 168 hours and administered small doses of alcohol. A further difference in deterioration of performance did not occur at higher doses of alcohol or later than 30 minutes after the dose was administered. While the percent of absorption of alcohol administered orally is greater with small doses than with the large, per unit of time, cold had no significant effect on over-all absorption rate. Rates of alcohol metabolism were not significantly altered by either acute or prolonged cold exposure, though body temperatures were altered significantly. When animals were habituated by receiving an aqueous solution of alcohol as their only source of fluid intake, equilibrium was impaired to a greater extent in some cold-exposed groups, the total increase in body weight per unit of time was depressed, the absorption rate was greater and oxidation rate slower than in groups habituated at room temperature. While the blood pentobarbital concentration was increased in animals exposed to cold for long periods, cold alone had no effect on the sleeping time induced by pentobarbital, and affected the increased sleeping time resulting from the simultaneous administration of alcohol and pentobarbital only when the two drugs were given within a short interval and the dose of alcohol was low. Chlorpromazine had a bivalent effect on body temperature, raising the temperature in animals exposed to cold and lowering the temperature in animals maintained at room temperature or when given to cold exposed animals in combination with alcohol. Cold had a brief effect on the impairment produced by alcohol and chlorpromazine together. Present data do not indicate a prolongation of the time during which performance is impaired due to the combined effects of chlorpromazine, ethyl alcohol, and cold.