The widespread practice of routine vaccination has greatly reduced the incidence of morbidity and mortality secondary to viral infection in the domestic canine population. Several viral infections of dogs may be implicated in both acute and chronic multisystemic disease processes, and the ocular manifestations associated with certain viral infections may be inconspicuous or profound. Susceptible animals include neonatal puppies with immature immune systems and immunocompromised adults that fail to mount an appropriate immune response to viral challenge. Ocular tissues can be damaged directly by intracellular viral replication or by the inflammatory effects of the associated cellmediated or humoral immune response to viral infection. Additionally, the eye can be affected by adverse immunologic responses that occur with some modified live viral vaccine products.