This protocol will permit the specialists in cornea and external disease at the NEI to identify, follow and provide "standard of care" treatment to patients with various corneal and external disease and anterior segment disorders. By providing long-term follow-up and treatment for a variety of corneal and external diseases, the corneal specialists at NEI will be better able to identify research hypotheses about these diseases in addition to maintaining their clinical skills. Another purpose of the protocol is to accumulate a cohort of patients with corneal diseases for possible participation in new NEI clinical trials and epidemiological protocols. The availability of cohorts of patients with a spectrum of anterior segment diseases will be valuable for the training of fellows, an important component of the mission of the NEI. The ability to provide follow-up and care will also facilitate referral efforts for NEI protocols.