This article reviews the theories and applications of acupuncture to musculoskeletal pain management. First, Chinese theories of acupuncture are discussed briefly. Next, current understanding of nociception and central pain modulation is discussed in detail,followed by discussion of the physiologic effect of acupuncture analgesia. Other theories of acupuncture analgesia are presented based on neuromodulation of the central nervous system. Finally,the efficacy of acupuncture for many musculoskeletal pain syndromes,including spine-related pain, soft tissue pain, neuropathic pain, arthritis of the knee, and upper extremity tendinitis, is reviewed. The article concludes with a discussion of methodologic issues related to conducting randomized, placebo-controlled trials of acupuncture and goals for future research in this area of pain management.