8 dogs were presented with the sound of a bell and the flash of a light in combination for 2 secs. 20 times during each of 10 test-periods. With 4 of these animals, left forelimb flexion from an electrically charged grid was conditioned to bell; with the other 4, flexion was conditioned to light. When light was given alone, the animals conditioned to bell responded to the light with forelimb flexion. When bell was given alone to the animals conditioned to light, it evoked a forelimb flexions-response. 2 control groups, given identical treatment to that of the experimental animals, except for the 200 trials of bell and light in contiguous combination, showed that generalization was not a factor in the response of the experimental animals to the stimulus never combined with shock. Evidence was thus obtained of an association or sensory conditioning of the bell and light.