Progress in antiviral chemotherapy has taken place as a logical strategy for the design of antiviral agents has emerged. The second-generation nucleoside analogues, led by acyclovir, have proved their worth against herpesviruses and should now become a standard part of medical practice. Meanwhile, recombinant DNA technology has lowered the cost of interferons to the point at which the several human subtypes of these naturally occurring hormones can be subjected individually to controlled clinical trials against the viral diseases in the treatment of which they show promise. Yet, optimism about the future of antiviral chemotherapy must be tempered by the observation that most of the agents discussed in this review are described more accurately as promising rather than proven, and several of these have not yet been released in Australia at the time of writing.