During each of 21 learning trials in a 2-compartment box, water-deprived rats were allowed to run to water reward. Foot shock was given in the water-bottle compartment on Trial 21. Within a period of 75, 300, 900, or 3,600 sec. after foot shock experimental rats were subjected to ECS (electroconvulsive shock). Latencies of entry by the ECS group into the water-bottle compartment, measured 21-24 hr. later, were shorter than those of a sham-ECS control group, the differences becoming less as the foot shock[long dash]ECS interval increased. Results are interpreted as favoring a consolidation hypothesis because effects due to fear and competing responses have been minimized.