In cranial electrotherapy stimulation (CES), micro-current levels of electrical stimulation are passed across the head via electrodes clipped to the ear lobes. After successful clinical use of CES with fibromyalgia patients in our clinic, it was decided to test these results with a double-blind, placebo-controlled study in which 60 randomly assigned patients were given 3 weeks of 1-hour-daily CES treatments, sham CES treatments, or were held as wait-in-line controls for any placebo effect in the sham-treated patients. Treated patients showed a 28% improvement in tender point scores, and a 27% improvement in self-rated scores of general pain level. The number of subjects rating their quality of sleep as poor dropped from 60% at the beginning of the study to 5%. In addition, there were significant gains in the self-rated feelings of well-being and quality of life, plus gains in six stress-related psychological test measures. No placebo effect was found among the sham-treated controls. A theoretical role of CES in affecting the brain's pain message mechanisms and/or neurohormonal control systems is discussed. It is concluded that CES is as effective as the drug therapies in several trials, with no negative side effects, and deserves further consideration as an additional agent for the treatment of fibromyalgia.