Preliminary results were reported for 22 patients (36 eyes with glaucoma) who had trabeculectomy. The procedure was successful in 32 eyes, but failed in 4 eyes. The patients ranged in age from 10-78 yr and their clinical courses were followed from 1-2 1/2 yr. Postoperative complications were mininal: a shallow chamber that spontaneously reformed; vitreous loss, which did not affect the outcome; and breakdown of the conjunctival flap, which reulted in loss of the bleb. The factors of age, sex and race (white and black) had no great significance, although more female patients formed belb and had control of intraocular pressure without medication than did male patients. The bleb was probably primarily a filtering structure. Trabeculectomy appears to be an effective surgical approach to the treatment of glaucoma. The surgical technique was described.