It has been generally accepted that the retropharyngeal wall protrudes into the lumen and forms a prominence during alaryngeal phonation. Although the prominence is thought to be responsible for the vibratory source, the relationship between the vocalization process and the dynamics of the prominence is not well known. This study is undertaken to clarify the above-described relationship during tracheoesophageal (TE) phonation, one of the most common forms of voice restoration following total laryngectomy. Electromyography (EMG) with simultaneous manometry and fiberoptic observation of the hypopharynx were done in 7 subjects who underwent TE fistulization at the time of laryngectomy. Fiberscopy revealed prephonatory closure of the hypopharyngeal lumen, and subsequently, a definite configuration of the lumen where diverted air can escape with mucosal vibration during phonation. The EMG disclosed a characteristic pattern that had two bursts of activity with an intervening quiet period. It may be concluded that TE phonation consists of two steps: The first step, associated with the first burst and regarded as the preparatory stage, consists of the hypopharyngeal closure which forms a small lumen. The second step, associated with the second burst and regarded as the phonatory stage, consists of the vibration of the neoglottis with a definite configuration which is maintained by the hypopharyngeal muscle contraction.