The use of complementary and alternative medicine (CAM) is widespread. Those with psychiatric disorders are more likely to use CAM than those with other diseases. There are both benefits and limitations to CAM. Many controlled studies have yielded promising results in the areas of chronic pain, insomnia, anxiety, and depression. There is sufficient evidence, for example, to support the use of a) acupuncture for addiction problems and chronic musculoskeletal pain, b) hypnosis for cancer pain and nausea, c) massage therapy for anxiety, and the use of d) mind-body techniques such as meditation, relaxation, and biofeedback for pain, insomnia, and anxiety. Large doses of vitamins, herbal supplements, and their interaction with conventional medications are areas of concern. Physicians must become informed practitioners so that they can provide appropriate and meaningful advice to patients concerning benefits and limitations of CAM.