Lymphoproliferative diseases affecting the lung occur over a broad clinical and pathologic spectrum. The clinical presentations and radiologic findings are nonspecific, entailing broad differential diagnoses. Accurate diagnosis requires adequate tissue sampling with appropriate ancillary pathologic studies. The recent delineation of new pathologic entities such as low-grade malignant lymphoma of mucosa-associated lymphoid tissue (MALT type) has aided in the understanding of the pathophysiology, clinical course, and management of patients with pulmonary lymphoma. Significant observations have been made in the clinical management and treatment of these disorders.