Indications for penetrating keratoplasty (PK) were assessed by clinicopathological review of 659 corneal buttons submitted from 1978 to 1987 to the Ophthalmic Pathology Service in Vancouver. Leading indications for PK were bullous keratopathy (22.2%), keratoconus (17.1%), scarring with or without chronic inflammation (13.5%), graft failure (12.1%), scarring or active keratitis secondary to virus (9.0%) and Fuchs' dystrophy (8.3%). The principal factors responsible for graft failure were also judged by clinicopathological correlation. The authors compare their findings with those in other series.