The early diagnosis of allergic bronchopulmonary aspergillosis (ABPA) is is important because it may allow prevention of evolution to the fibrotic lung disease stage (stage V). In two immunotherapy studies of 62 patients recruited for allergic rhinitis, we conducted studies to exclude ABPA in any subject with asthma and positive immediate skin reactivity to Aspergillus fumigatus. The evaluation included serum precipitating antibodies against A. fumigatus, total serum IgE, blood eosinophilia, serum IgE and IgG antibody indices against A. fumigatus, and chest X-rays. Three of the 62 patients (5%) had features indicative of ABPA. This finding underscores the importance of excluding the diagnosis of ABPA in all asthmatics with skin reactivity to A. fumigatus, even if the patients major initial complaint is allergic rhinitis.