Thirteen patients with refractory glaucoma following penetrating keratoplasty were treated with 180 degree transscleral Neodymium: YAG cyclophotocoagulation. Intraocular pressures below 21 mmHg were achieved in nine patients (69%) with a mean follow up of 19.8 months. Multiple treatments were required in six patients and graft decompensation occurred in five. No patient developed hypotony. Transscleral YAG cyclophotocoagulation is a useful alternative to further surgery in some patients with glaucoma following penetrating keratoplasty.