To determine the incidence and clinical manifestations of herpes zoster in a hospital-based clinic for adults infected with human immunodeficiency virus (HIV), we reviewed the records of all patients for whom zoster was diagnosed at or after their first clinic visit. Fifty-two episodes of zoster occurred in 45 patients during 1,614 person-years of follow-up (incidence, 3.2 episodes per 100 person-years). The following major complications of zoster occurred in 12 patients (27%): ocular complications (5), neurological complications (4), and chronic atypical skin lesions (5). Six patients each had postherpetic neuralgia and bacterial superinfection, which were the common minor complications of zoster. Multivariate analysis revealed that only a low CD4 cell count (< or = 200/mm3) was predictive of a major complication of zoster (OR, 13.2; 95% CI, 1.52-114; P = .019). Thus, complications of herpes zoster are common in patients with HIV infection, especially those with advanced immunosuppression.