HEDS-II consists of two randomized, placebo-controlled trials that are assessing the role of oral acyclovir in the management of herpetic eye disease and one epidemiologic study that is investigating risk factors, including stress, for the development of ocular recurrences of the disease. The organizational structure consists of a national coordinating center, eight regional coordinating clinical centers, and approximately 60 clinical sites. The clinical sites where patients are enrolled and followed include both university-based and community-based practices.