The malignant lymphomas include at least 30 entities that are distinct with respect to histology, immunology, genetics, clinical features, and outcome following therapy. The clinical behavior of these diseases ranges from indolent but generally incurable to aggressive and frequently fatal yet potentially curable with appropriate chemotherapy or chemotherapy-antibody regimens. Over the past 50 years, the Cancer and Leukemia Group B (CALGB) Lymphoma Committee has conducted a series of clinical trials that have contributed to an improvement in outcome for patients with a number of the more common lymphoma subtypes. The World Health Organization has classified approximately 30 neoplastic diseases of the hematopoietic and lymphoid tissues (1). The Cancer and Leukemia Group B (CALGB) Lymphoma Committee highlight below clinical trials that have resulted in improved patient outcome for the more frequent lymphoma subtypes.