In an effort to achieve the early postoperative safety and stability provided by trabeculectomy plus the late lower intraocular pressure (IOP) advantages of full-thickness glaucoma filtration surgery, 43 eyes of 38 patients with chronic open-angle glaucoma had laser suture lysis after primary trabeculectomy. The technique of laser suture lysis afforded serial release of resistance to aqueous outflow through the newly performed trabeculectomy, allowing initial tight closure of the trabeculectomy to avoid the dangers of hypotony. Serial gradual loosening of the trabeculectomy closure decreased resistance to outflow through the trabeculectomy and thereby lowered the IOP to desired levels in a controlled, titrated manner. Complications decreased with experience. For 25 eyes with at least 6 months follow-up (average, 54 weeks), the average IOP decreased from 25.0 mmHg preoperatively to 12.2 mmHg postoperatively.