Background/aims To determine the medium-term intraocular pressure (IOP) control and visual outcomes for patients with advanced glaucoma undergoing trabeculectomy with mitomycin C. Methods All patients with advanced glaucoma (MD −20 dB or above) undergoing trabeculectomy with mitomycin C between 2000 and 2008 under the care of a single glaucoma surgeon were included. IOP, visual acuity and visual field outcomes were assessed from data prospectively collected into a surgical outcome database. Results 103 patients were eligible for inclusion. The post-trabeculectomy group mean IOP varied between 11.3 and 13.3 mm Hg between 1 and 7 years. At year 5, 85.2% had an IOP of Conclusion Trabeculectomy is a successsful method of controlling IOP in the short to medium term in patients with advanced glaucoma.