As a case in point, we consulted on a 62-year-old male music teacher and professional saxophone player who sought care for a low-grade fever associated with fatigue and a dry cough. He had no other significant medical history. Physical examination was notable for bibasilar inspiratory rales. A panel of autoantibody tests was negative. Pulmonary function tests demonstrated normal spirometry, borderline lung volumes (total lung capacity, 81% predicted), and impaired diffusion capacity of the lung for carbon monoxide (62% predicted). High-resolution CT scan revealed subpleural reticulation, mild architectural distortion, and bronchiolectasis within the middle and lower lung zones. A surgical lung biopsy specimen demonstrated patchy interstitial fibrosis around the small airways accompanied by small lymphoid aggregates, multinucleated giant cells, and numerous loosely formed granulomas in a peribronchiolar distribution. This pattern was diagnostic for HP.