A technique is described for the collection of tracheobronchial secretions from the upper trachea of anesthetized dogs. The method is simple, relatively quantitative, and provides secretory material in quantity suitable for biochemical or rheological studies. In 42 experiments comprising 184 individual samples we have found the collection rate of tracheobronchial secretions to be 1.0 ± 0.1 mg/min per kg (mean ± SEM). airway mucus; trachea; anesthetized dogs Submitted on June 11, 1975