Fifty percent of patients with ophthalmic zoster develop ocular complications. These may be mild or severe, and can lead to loss of sight which, by timely and good management can be prevented in most cases. Unfortunately knowledge of the complications and their management is often poor making the design and interpretation of clinical trials difficult. 1356 cases of ophthalmic zoster were collected over fifteen years with at least 6 months follow up. Their details and complications were entered into a database. There is a generally held impression that patients developing zoster do so because of impaired immunity. Analysis of our findings showed that this was not so. The database results were analyzed to quantify the incidence of complications and their correlates. Two common corneal complications that are difficult to manage and lead to visual impairment were studied in detail including: Mucous plaque keratitis is defined as a distinct entity appearing at an early or late stage and occurred in forty seven cases. Poor management leads to visual impairment from neurotrophic ulceration, megaplaque keratitis and glaucoma. Lipid keratopathy induces diminished visual acuity and photophobia. It occurred in thirty six cases. Careful and prolonged treatment of chronic stromal keratitis with topical steroid will prevent this occurring, but when it does successful laser occlusion of corneal blood vessels halts the deposition of lipid and may actually disperse it or make the host cornea safer for keratoplasty. One hundred and seventy six patients were screened orthoptically and the incidence of extraocular muscle palsies assessed with regard to distribution and natural history. Possible pathogeneses are discussed. Overall recovery was good. Lastly iritis and iris atrophy were identified in five hundred and twenty patients and twenty three were investigated with anterior segment fluorescein angiography. This showed that they were associated with an ischaemic vasculitis.