In studying the relationship between level of CS intensity (light) and drug condition (amobarbital sodium) in the acquisition of the conditioned avoidance response of the white rat in a jump-box task, data showed that both variables influenced avoidance performance. Although the over-all performance of drugged Ss was better than that of those given a placebo, primary differences occurred at 50,000 and 800,000 peak candles of CS intensity; performance of Ss under placebo showed a marked decline at 800,000 peak candles.