We studied the ultrastructure and function of respiratory tract cilia in a group of patients with Kartagener's Syndrome, and compared the results with those from a group of subjects with unexplained histories of chronic bronchiectasis and bronchitis. Both patient groups lacked pulmonary and nasal mucociliary transport. On electron microscopic examination of nasal mucosal biopsy tissue, all patient specimens had abnormal cilia with a highly disorganized microtubular network, and a consistent absence of dynein arms. Cilia from both groups were immotile when viewed under direct phase contrast, but could be animated by the addition of 10(-6) g/ml of ATP or ATPase to the same degree of spontaneous motility seen in normal cilia. Immotile cilia syndrome clearly includes not only patients with Kartagener's syndrome, but also some patients with chronic bronchitis and bronchiectasis.