One nonpharmacological intervention that has gained increasing support in the last two decades is therapeutic touch. Therapeutic touch, also referred to as healing touch and touch therapy, is a complementary and alternative treatment in which practitioners seek to alleviate or reduce pain, stress, or anxiety through direct hand contact with a client's bio- or energy field. A bio- or energy field is defined in quantum physics as an interconnected web of energy that surrounds living organisms and may regulate emotional states and physical health. Although the existence of energy fields is increasingly accepted in the scientific community, the precise roles of and mechanisms through which energy fields work are not understood. While eastern health practitioners have for centuries used therapies addressing energy fields—for example, acupuncture, acupressure, Ayurveda, qi gong—western practitioners have only begun using such therapies in the last century. The most common western names for energy field therapy are therapeutic touch, healing touch, Reiki, and touch therapy—all of which have growing bodies of evidence supporting their effectiveness in the reduction of stress, anxiety, and pain in various diagnostic populations including cancer, cardiovascular disease, and chronic pain syndromes.