Single unit cerebellar Purkinje cell activity was recorded extracellularly in urethane-anaesthetised rats. An inhibition of these cells, believed to be GABA-mediated, which is produced by local surface stimulation of the cerebellar cortex was antagonized by the local, micropressure application of ethanol. The inhibition of cerebellar Purkinje cells produced by local micropressure application of GABA was similarly antagonized by a slow i.v. infusion of ethanol (1.5 g/kg over 10 min). When both ethanol and GABA were applied to the Purkinje cells by local micropressure the results were difficult to interpret due to an ethanol-induced decrease in the baseline firing rate. There was a decrease in the absolute GABA-mediated inhibition but no change in the relative inhibition. In general, it appears that ethanol produces an antagonism of GABA-mediated inhibition of cerebellar Purkinje cells.