Nine adult patients from three community teaching hospitals had bronchospasm unresponsive to standard therapy. Bronchoscopic, cytologic, histopathologic, and virologic studies confirmed that necrotizing and exudative tracheobronchitis was due to herpes simplex virus. No patient had a history of previous chronic lung disease; most were not immunocompromised. Three patients never had intubation during hospitalization. All patients were successfully treated with intravenous acyclovir. Herpetic tracheobronchitis may be a commoner clinical syndrome than generally assumed. In an elderly patient with unresolving acute bronchospasm, herpesvirus infection of the lower respiratory tract should be considered in the differential diagnosis. In the immunocompetent host, antiviral therapy can successfully treat herpesvirus respiratory infection, with reversal of clinical, virologic, and pathologic findings. A prompt and accurate diagnosis is crucial.