Pulmonary aspergillosis refers to a spectrum of diseases resulting from Aspergillus becoming resident in the lung. These include invasive aspergillosis from angioinvasive disease, simple aspergilloma from inert colonization of pulmonary cavities, and chronic cavitary pulmonary aspergillosis from fungal germination and immune activation. Chronic pulmonary aspergillosis includes simple aspergilloma, which is occasionally complicated by life-threatening hemoptysis, and progressive destructive cavitary disease requiring antifungal therapy. Allergic bronchopulmonary aspergillosis occurs almost exclusively in patients with asthma or cystic ﬁbrosis. Invasive aspergillosis is now recognized to occur in patients with critical illness without neutropenia and in those with mild degrees of immunosuppression, including from corticosteroid use in the setting of COPD. Improvement in outcomes for Aspergillus pulmonary syndromes requires that physicians recognize the varied and sometimes subtle presentations, be aware of populations at risk of illness, and institute potentially life-saving therapies early in the disease course.