Primary ciliary dyskinesia represents a group of heritable disorders of cilia and sperm affecting between 1 in 15,000 and 1 in 30,000 persons. Those affected lack measurable mucociliary clearance and suffer the constant misery of rhinorrhea and chronic productive cough. Because mucociliary clearance constitutes one of the respiratory system's major lines of defense, these patients are vulnerable to chronic sinusitis, bronchitis, pneumonia, and otitis media. Left untreated, these problems may progress to bronchiectasis, found frequently in adult patients, or pulmonary hypertension with eventual cor pulmonale. Screening for this disorder includes some simple and inexpensive methods as well as more exotic techniques requiring special camera equipment and an electron microscope to make a definitive diagnosis. Physiotherapy techniques can be taught to patients with primary ciliary dyskinesia and go a long way toward making up for the lack of mucociliary clearance. Vigorous bronchopulmonary toilet and palliative measures may enable these patients to enjoy relatively normal lives.