Complex regional pain syndrome (CRPS) is a progressive, chronic illness that is enigmatic because the mechanisms for its pathogenesis have yet to be determined. Syndromes synonymous with CRPS are reflex sympathetic dystrophy, reflex neurovascular dystrophy, causalgia, algoneurodystrophy, sympathetically maintained pain, clenched fist syndrome, and Sudek's syndrome. The diagnosis of CRPS is categorized into three stages: acute, dystrophic, and atrophic. CRPS is most often precipitated by peripheral trauma (crushing injuries, lacerations, fractures, sprains, burns, or surgery) to soft tissue or nerve complexes. The pathogenesis for CRPS has been speculated as being either a disease process of the peripheral nerves, a disease process of peripheral soft tissue, or a disease process of the spinal cord. Patients suffering from CRPS may be limited in their ability to function in a self-directed, independent fashion. A longitudinal study of CRPS on 1,348 patients revealed that 96% of the study subjects still suffer some pain and disability regardless of the duration of the disease or course of treatment. Although the primary etiology for CRPS is not clearly understood, key progress has been made in terms of establishing a psychological as well as therapeutic treatment plan once the diagnosis has been made.