Medical treatment has always been the mainstay in the management of primary open-angle glaucoma (POAG). Surgical intervention has been reserved for cases with intraocular pressures uncontrolled on medical therapy and/or progression of visual field loss. Following the introduction of trabeculectomy, there was a move toward earlier surgery in POAG with some advocating it as a primary procedure. However, others have emphasised the complications and unpredictability of trabeculectomy and use it only as a last resort. In this article the literature is reviewed and the factors that prevent complications and help ensure a successful result in trabeculectomy are considered. While the role of trabeculectomy as a primary procedure in POAG is debatable, the authors favour earlier surgical intervention rather than using surgery as a last resort.