We compared the results achieved in 22 consecutive patients who underwent single-plate Molteno implantation, with those achieved in a matched group who had trabeculectomy with postoperative 5-fluorouracil. Six months following surgery, the average intraocular pressure (IOP) in the Molteno group was 15.4 +/- 8.0 mm Hg, and in the trabeculectomy group, 16.1 +/- 5.6 mm Hg (P = .920). A mean of 1.4 antiglaucoma medications were being used in each group (P = .776). Complications following Molteno implantation included six tube revisions and three flat anterior chambers; following trabeculectomy, eight serous choroidal detachments and nine positive Seidel tests. This study suggests that Molteno implantation and trabeculectomy with adjunctive 5-fluorouracil provide similar IOP control, but that the two procedures are associated with different types of complications.