Nd:YAG laser cyclophotocoagulation (CPC) of the ciliary body is a promising cyclodestructive treatment for the management of refractory glaucoma following penetrating keratoplasty. Twenty-eight eyes (27 patients) were treated between August 1985 and September 1987 and followed 6 to 24 months (median, 18 months). The mean intraocular pressure (IOP) was initially 39 mm Hg (range, 30 to 70 mm Hg) on maximally tolerated medications. The Lasag Microrupter 2 was used in the free-running thermal mode with a mean pulse energy of 4.13 J. The laser was retrofocused 3.6 mm from the conjunctival surface and 30 to 50 applications per treatment (mean, 37.5) were given 2 to 3 mm from the limbus for 360 degrees (71%) or 180 degrees (29%). Multiple treatments were necessary in 13 eyes (46%). After CPC, IOP fell to 22 mm Hg or below in 18 eyes (64%) at 3 months, in 20 of 27 eyes (74%) at 6 months, and in 16 to 24 eyes (67%) at 1 year. Inadequate IOP control in four of 28 eyes necessitated cyclocryotherapy in three patients and a Schocket procedure in one other. Of the 14 clear pre-CPC grafts six (43%) became edematous during follow-up. All of the failed grafts had undergone multiple CPCs.