Five normal-speaking adult males were taught to produce speech using an electrolarynx. Speech phoneme intelligibility was measured in a closed-set word discrimination test and through phonetic transcriptions of the spoken materials. Mean percentages of correct identification for the five talkers were 90% and 57% for the word-identification test and phonetic transcription, respectively. An analysis of perceptual confusions revealed that errors were most frequently associated with the voicing feature and that few manner or place of articulation errors occurred. Over the range of variables observed, the intensity of both the speech and the noise radiating directly from the electrolarynx, the spectrum of the radiated noise and speaking rate were not found to be determinants of intelligibility.