Over a two-year period the families of twenty-five children with cancer and of a comparison group of children brought to a general pediatric clinic were studied by means of the Holmes-Rahe Life Schedule of Recent Events and by personal interviews. Results obtained by use of the Holmes-Rahe questionnaire revealed significant differences between the patient and control groups. Histories obtained from families in both groups also revealed that in the cancer group certain important life events were found to have occurred with greater frequency in the year prior to the onset of the disease. The relevance of these findings to previous work done in the field and to some current theories concerning the relationship of genetic, viral, endocrine, and psychological factors in the development of cancer are discussed.