Forty-five patients with symptomatic proximal malignant airway disease received 128 intraluminal intermediate dose rate (IDR) brachytherapy treatments by remote afterloading technique. Multiple small catheters were bronchoscopically placed. Iridium-192 sources delivering an intermediate dose rate (200-1000 rads/hr) were guided under remote computer control. Treatment times were 1-4 hr. Fourteen of these patients also received YAG laser photoresection. External beam radiation was also given (6000 rads) to 16 patients for curative intent and (3000 rads) to 9 patients for palliative intent. Twenty recurrent disease patients were also treated, but they did not receive external irradiation. An obstruction score (OS) was developed in an attempt to quantitate the improvement in intraluminal narrowing. Patients treated with curative intent showed 66% improvement after initial therapy. Initial therapy for palliative patients showed an 84% improvement and for recurrent disease patients, 64% of luminal narrowing was seen. Patients who received laser in addition to brachytherapy showed a 70% reduction. A 67% improvement was seen in those who did not receive laser therapy. The entire group averaged a 69% improvement of narrowing. Four complications, three minor, (1 bronchospasm, and 2 episodes of transient intratreatment increased ventricular irritability) and one major (pneumothorax) were noted. The relatively short treatment times allowed most of the treatments to be performed on an outpatient basis and were well-tolerated by the patients. Forty-four of the 45 patients experienced significant symptomatic improvement. The remote afterloading technique allowed improved radiation protection for personnel.