<h3>To the Editor.—</h3> Acyclovir-resistant herpes simplex virus (HSV) in human immunodeficiency virus (HIV)-infected patients has been reported, often after long-term therapy with acyclovir.<sup>1</sup>In some cases the lesions responded to foscarnet (trisodium phosphonoformate) therapy.<sup>1</sup>Acyclovir-resistant varicella zoster virus (VZV) has also been reported with increasing frequency in HIV-infected patients, and is commonly associated with chronic localized verrucous skin lesions.<sup>2,3</sup>Although in vitro sensitivity to foscarnet has been reported, we believe that this is the first report in which chronic lesions due to acyclovir-resistant varicella zoster virus have resolved after treatment with foscarnet. <h3>Report of a Case.—</h3> A 24-year-old white man with acquired HIV infection (Walter Reed Stage VI) presented with a history of herpes-zoster occurring in the left C7-8 dermatome in July 1989. The cutaneous lesions were typical vesicular lesions of VZV. The patient was treated with high-dose oral acyclovir (4 g/d for 10 days) with apparent