This pUblication contains the Review Lectures presented at a joint NATO Advanced Study Institute and FEES Advanced Study Course held at Les Arcs, Bourg-8aint-Maurice, France, from the 19th June - 2nd July 1983. The Course, entitled "Targets for the Design of Antiviral Agents" was in some ways a sequel to the NATO-FEES Course held at SOGESTA (near Urbino), Italy from the 7th - 18th May 1979 and published as volume A26 in this series. During the subsequent...