The monopoly held by aciclovir in the treatment of herpes infections is about to crumble. The first challenge comes from famciclovir [Famvir®; SmithKline Beecham], which was recently launched for the treatment of herpes zoster. Valaciclovir [ValtrexTM; Wellcome; preregistration] looks set to follow shortly, and several other agents are under development. SmithKline Beecham is also making good progress with its gD2t vaccine, which is about to enter phase III trials [see boxed text]. The current state of play in herpes-related therapy was discussed during several presentations at the 34th Interscience Conference on Antimicrobial Agents and Chemotherapy [Orlando, US; October 1994].