Although there have been many successful, controlled demonstrations of the clinical efficacy of multicomponent treatments for irritable bowel syndrome (IBS), in the present study we sought to evaluate a single component of many of these regimens, relaxation training. Eight IBS patients received a 10-session (over 8 weeks) regimen of abbreviated progressive muscle relaxation with regular home practice while 8 comparable patients merely monitored GI symptoms. Based on daily GI symptom diaries collected for 4 weeks before and 4 weeks after treatment (or continued symptom monitoring), the Relaxation condition showed significantly (p = .05) more improvement on a composite measure of primary GI symptom reduction than the Symptom Monitoring condition. Fifty percent of the Relaxation group were clinically improved at the end of treatment.