More than 10% of the 700,000 American troops who served during the first Gulf War (GW) are receiving treatment for a constellation of diffuse and frequently poorly defined medical and psychiatric symptoms that have been designated the GW syndrome by both clinicians and the popular media. The current clinical consensus is that the symptoms reported in GW veterans are the sequela of combat and other stressful events that have been identified in the veterans of other wars and armed conflicts. Chronic diffuse pain is one constellation of symptoms commonly reported in GW veterans. Research has confirmed a close bimodal relationship between chronic pain and psychiatric symptoms. Investigators are now exploring the efficacy of treatment approaches that address the close relationship between chronic pain and mental illness in this challenging patient population.