Chronic fatigue syndrome (CFS) is characterized by debilitating fatigue and a variety of somatic symptoms. Few studies have examined psychological aspects of CFS. In the present study, self-efficacy is shown to be a significant predictor of CFS symptoms beyond the variance accounted for by demographic variables and distress. Further psychological CFS research is encouraged by (1) identifying dimensions that are salient in the experience and study of CFS, (2) providing preliminary psychometric data for measures of those dimensions, and (3) identifying psychological variables that serve as moderators of the experience of CFS.