The number of useful antiviral compounds is rapidly expanding. The current antiviral agents FactFile is a convenient key to the vital statistics of antiviral compounds to be used as an aide mémoire when reading or writing antiviral literature. A mini-portrait is provided for each of the antiviral compounds. The minimum criteria for inclusion of new compounds in the FactFile is the granting of an investigational new drug application with the realistic potential for medical or veterinary application. Several compounds that were subsequently withdrawn from further development are also included because of their historical importance or particular interest. The compounds are listed alphabetically according to their generic names together with systematic chemical names, common names and chemical structures. The compounds are grouped by virus targets; thus, the list is sub-divided into inhibitors of DNA viruses, RNA viruses, and retroviruses. The authors welcome comments and suggestions to be incorporated in future editions of the FactFile.