The Rye classification has been applied to 184 cases of Hodgkin's disease diagnosed in one of the largest hospitals of Rome, Italy, over a period of three years. Mixed cellularity was the most common histologic type. Nodular sclerosis had an intermediate frequency, while lymphocyte predominance and lymphocyte depletion showed the lowest incidence. There was a male predominance in almost all age groups, reflecting a total male to female ratio of 1.5:1. The most frequent sites of primary involvement were cervical, supraclavicular, and axillary nodes, while mediastinal nodes were found primarily involved in a limited number of cases. Incidence, results, and anatomic distribution of lesions were evaluated in 120 untreated patients who underwent staging procedures. A correlation was found between increasing histologic malignancy and abdominal spread of the disease. The most common form of abdominal disease was the simultaneous involvement of two or more tissues, and the association most frequently observed was that of lymph nodes and the spleen. Separate infiltration of the liver was rare, while involvement of bone marrow only was never observed.