Objective To evaluate the efficacy and safety of current trabeculectomy surgery in the United Kingdom. Design Cross-sectional, multicenter, retrospective follow-up. Participants A total of 428 eyes of 395 patients. Methods Consecutive trabeculectomy cases with open-angle glaucoma and no previous incisional glaucoma surgery from 9 glaucoma units were evaluated retrospectively. Follow-up was a minimum of 2 years. Main Outcome Measures Surgical success, intraocular pressure (IOP), visual acuity, complications, and interventions. Success was stratified according to IOP, use of hypotensive medications, bleb needling, and resuturing/revision for hypotony. Reoperation for glaucoma and loss of perception of light were classified as failures. Results Antifibrotics were used in 400 cases (93%): mitomycin C (MMC) in 271 (63%), 5-fluorouracil (5-FU) in 129 (30%), and no antifibrotic in 28 (7%). At 2 years, IOP (mean ± standard deviation) was 12.4±4 mmHg, and 342 patients (80%) achieved an IOP ≤21 mmHg and 20% reduction of preoperative IOP without IOP-lowering medication, whereas 374 patients (87%) achieved an IOP ≤21 mmHg and 20% reduction of preoperative IOP overall. An IOP ≤18 mmHg and 20% reduction of preoperative IOP were achieved by 337 trabeculectomies (78%) without IOP-lowering treatment and by 367 trabeculectomies (86%) including hypotensive medication. Postoperative treatments included suture manipulation in 184 patients (43%), resuturing or revision for hypotony in 30 patients (7%), bleb needling in 71 patients (17%), and cataract extraction in 111 of 363 patients (31%). Subconjunctival 5-FU injection was performed postoperatively in 119 patients (28%). Visual loss of >2 Snellen lines occurred in 24 of 428 patients (5.6%). A total of 31 of the 428 patients (7.2%) had late-onset hypotony (IOP <6 mmHg after 6 months). In 3 of these, visual acuity decreased by >2 Snellen lines. Bleb leaks were observed in 59 cases (14%), 56 (95%) of which occurred within 3 months. Two patients developed blebitis. Bleb-related endophthalmitis developed in 1 patient within 1 month postoperatively and in 1 patient at 3 years. There was an endophthalmitis associated with subsequent cataract surgery. Conclusions This survey shows that good trabeculectomy outcomes with low rates of surgical complications can be achieved, but intensive proactive postoperative care is required. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.