To evaluate the efficacy of the Ahmed valve implant in patients with uncontrolled uveitic glaucoma, the medical records of all patients with uncontrolled uveitic glaucoma who underwent Ahmed valve implant surgery between October 1993 and March 1996 were reviewed. Surgery was considered a success if intraocular pressure (IOP) was less than 22 mmHg and greater than 4 mmHg (with or without antiglaucoma medications) at the last postoperative visit. It was not a success when further glaucoma surgery had been performed, or chronic hypotony, phthisis, or loss of light perception occurred. Fourteen patients (14 eyes) with a mean age of 45.7 years were included. Most of them were high-risk patients, many of whom had already had cataract surgery (71.4%) and undergone one to three previous glaucoma surgeries (57.1%). Follow-up for eyes in which IOP was controlled ranged from 11 to 40 months (mean 22.6 months). Success was achieved in eight of 14 eyes (57.14%). Intraocular pressure was reduced from a mean of 32.64 +/- 7.79 mmHg (range 23-46 mmHg) with 2.78 +/- 0.57 antiglaucoma medications (range 2-4) preoperatively to 17.57 +/- 10.93 mmHg (range 0-38 mmHg) (p < 0.0001) with 0.71 +/- 0.99 antiglaucoma medications (range 0-3) postoperatively (p < 0.0001). The most common complications were encapsulated bleb in six eyes (42.8%), transient hypotony in six eyes (42.8%), and hyphema in three (21.4%). Ahmed valve implant appeared to be a safe alternative in high-risk patients with uncontrolled uveitic glaucoma who have had multiple previous ocular surgeries.