We analyzed 740 penetrating keratoplasty specimens received at the Intermountain Ocular Research Center from 1981 through 1988. These corneal specimens were categorized by clinical indications for removal and pathologic confirmation of the clinical findings. Keratoconus was the most common indication for a penetrating keratoplasty (22.8%). This was closely followed by pseudophakie bullous keratopathy (21.8%), regraft (13.2%), scarring (8.9%), aphakic bullous keratopathy (6.4%), and Fuchs' endothelial dystrophy (5.8%). Since 1984, pseudophakic bullous keratopathy has surpassed keratoconus as the most common indication for penetrating keratoplasty (27.3% vs. 20.2%). Pseudophakic bullous keratopathy was found more commonly than keratoconus in each of the last four years of this study. The most common type of intraocular lens associated with pseudophakic bullous keratopathy was an anterior chamber lens (52.8%), with iris-fixated (26.7%) and posterior chamber (17.4%) lenses seen less frequently.