We have previously described surgical techniques for draining severe cases of secondary glaucoma by means of an artificial implant. Wherever possible these implants have been inserted in two stages. The technique involved suturing the episcleral plates of the implant to the sclera without connecting them to the chamber as the first procedure. Following this procedure the presence of the plates cause the surrounding tissue to form a thin fibrous envelope called a preformed bleb cavity. After a suitable interval of between six and eight weeks the connecting tube of the implant was inserted into the anterio chamber so as to drain aqueous into this preformed bleb cavity. This manoeuvre drastically reduced the incidence of postoperative hypotony and has proved a safe and effective technique. This communication reports an improvement on this technique in which the connecting tube of the implant is occluded by a ligature of 5-0 vicryl before inserting the tube into the anterior chamber through a fine needle puncture, at the same time as the episcleral plates of the implant are sutured to the sclera. The effect of this procedure is thus to prevent any drainage of aqueous until three to five weeks after operation when the vicryl suture material dissolves, allowing aqueous to drain into the preformed bleb system lined by a thin layer of dense fibrous tissue. This technique provides the advantages of the previous two-stage technique without the need for a second operation. The surgical technique is described together with the results of treating a series of 20 eyes with severe secondary glaucoma.