The pathologic findings in 117 untreated patients subjected to laparotomy for the staging of Hodgkin's disease, at Stanford University Medical Center, were correlated with the preoperative clinical evaluation. The validity and applicability of the modified classification of Lukes, Butler, and Hicks were confirmed, and the consistency of the histologic pattern in multiple lesions was verified. Nodular sclerosis was the most frequent histologic type encountered and showed a predilection for the mediastinum (81%), with a high incidence of abdominal involvement (39%). The recognition of a cellular phase within the spectrum of nodular sclerosing Hodgkin's disease by virtue of the presence of characteristic “lacunar cell” with minimal or absent sclerosis, appeared to be justified by the observation of typical sclerosis in other lesions from the same patient. Occult abdominal disease was most often located in the spleen and the splenic hilar lymph nodes. Focal and microscopic involvement of abdominal lymph nodes was frequently observed. with partial preservation of the nodal architecture. Preoperative evaluation of the spleen was inaccurate in one third of the cases. Liver function tests were unreliable indicators of hepatic disease, whereas interpretation of the lymphangiogram was generally accurate below the level of the second lumbar vertebra. Abdominal involvement was encountered only once in the absence of left cervical lymph node disease. The observation of isolated granulomas in 14% of cases was not considered evidence of Hodgkin's disease or Boeck's sarcoidosis.