An experimental intravitreal sustained-release device containing ganciclovir was used to treat 22 patients with acquired immunodeficiency syndrome-associated cytomegalovirus retinitis. Fourteen eyes were excluded (five not involved and nine with macular scarring and/or severe debility). Thirty eyes received the ganciclovir intraocular device implant and were prospectively followed up from 16 to 419 days (median, 125 days). Twenty-seven (90%) of 30 eyes showed stabilization of the retinitis. Nine (33%) of 27 eyes showed reactivation of the retinitis once the device was empty of ganciclovir; seven received a replacement device, with subsequent stabilization of the retinitis. Postoperative complications included vitreous hemorrhage (n = 1), endophthalmitis (n = 1), and progressive retinitis (n = 2). Late retinal detachment was seen in three eyes (11%) at 35 to 140 days. Survival analysis of all 30 eyes revealed the mean time to progression of retinitis to be 19 weeks (133 days). The ganciclovir intraocular device offers a promising alternative for the treatment of cytomegalovirus retinitis associated with acquired immunodeficiency syndrome.