The brains of 22 anesthetized chickens were systematically explored with stimulating electrodes for electrically-evoked vocalizations. Both active and inactive areas for evoked vocalizations as determined from 821 electrode penetrations were plotted. An apparently continuous system, active for vocalization, extends from the preoptic region rostrally to the most caudal portion of the medulla posteriorly. All portions of the striatum and spinal cord sampled were negative for vocalizations at the stimulus intensity used. Thresholds were lowest; calling was the most natural sounding and was elicited in the absence of other behavior in the area ventro-medial to the inferior colliculus. Most of the brain yielded only repetitive vocalizations ranging from brief ''cuk'' sounds to longer duration squawk sounds similar to those given by normal chickens. In the medulla both repetitive sounds in response to continuous stimulation and single protracted sounds per stimulation were evoked. Both types of vocalization could be elicited from the same site by varying the stimulus intensity. In portions of the midbrain, pons and medulla vocalization substrates corresponded to areas reported to yield respiratory responses in this and other species. Results are in agreement with those reported for chronically-implanted awake birds and are interpreted to suggest a single set of neural mechanisms controlling the production of vocalizations.