Hodgkin's lymphoma (HL) accounts for 1% of cancers and is of largely unknown pathogenesis. This study intended to find clues about potential causes (etiology) of HL through observations on patients and their families. In 37 years of a medical oncology practice in Basel, Switzerland, 36 out of 2201 patients (1.6%) had HL. Etiological information has been obtained from the patients with the help of a German translation of the NCI Medical History Questionnaire for Cancer Etiology, and through the study of their medical charts. Findings of etiological interest were observed in the medical history of 26 out of the 36 patients with HL; these findings were grouped as follows: benign tumors (25%), carcinogenic exposures (19%), immunologic disorders (19%), secondary malignancies (14%), infections (11%), congenital disorders (8%) and tonsillectomies (6%). Twenty-two out of 36 patients had one or more relatives with cancer. Personal and family history of patients with HL is a readily available useful tool for etiology research. The fact that HL is frequently associated with other cancers in patients and their relatives points to causal genetic factors. Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.