This study was undertaken to describe the self-care burden (SCB) of persons receiving radiation as outpatients, to identify factors contributing to SCB, and to test a model of the effects of SCB, symptom distress, and appraisal of illness on mood. The subjects were 72 adults with cancer who had been in treatment an average of 4 weeks. Fatigue was reported to be the most distressing symptom. Among health deviation self-care tasks, coming for treatment was the most demanding, and self-treatment, such as administering medications, was the most difficult. Universal self-care activities most disrupted by treatment were social and recreational activities. Path analysis revealed that dependency was the primary predictor of health deviation SCB, while symptom distress was the best predictor of universal SCB. Universal SCB and family hardiness were the best predictors of appraisal scores. Symptom distress and somatic mood were highly correlated, suggesting collinearity between these factors. Four variables--appraisal, symptom distress, family hardiness, and health deviation SCB--explained 55% of the variance in affective mood scores. Theoretical and clinical implications are discussed.