Bronchiectasis is a chronic disease with a variety of aetiologies that influence the clinical presentation and management of the disease. One of these aetiologies is allergic bronchopulmonary aspergillosis (ABPA). Methods: 27 of 1000 patients (2.7%) included in PROGNOSIS had ABPA as aetiology of bronchiectasis (per investigator judgment). ABPA testing was the most common aetiological test performed in 58% of subjects. Comparison was made to 973 adults with bronchiectasis caused by any other aetiology. Results: Mean age was 63 years in ABPA compared to 61 years (p=0.410), 37% were male (vs 41%; p=0.694). Median annual exacerbation rate was 2 (each; p=0.47). Although mean ppFEV1 differed from 59.7% (95% CI: 52.5-77.0) to 70.6% (95% CI: 66.9-71.3), there was no significant difference (p=0.842). Radiological features showed predominant involvement of upper lobes (left 70.4% vs. 35.5%, p Method: Adults with ABPA as aetiology of bronchiectasis show mainly upper lobe involvement and cystic bronchiectasis with no differences in frequency of positive fungal cultures. The majority is treated with OCS, only two-thirds received ICS, antimycotics were infrequently used. Further research is warranted, especially as ABPA is considered a treatable trait in bronchiectasis.