Acupuncture, which originated in China more than 2,500 years ago, is regulated in Ontario by the College of Traditional Chinese Medicine (TCM). Influenced by ancient Chinese philosophy, culture, and science and technology, two concepts that are fundamental to TCM are qi (vital energy) and yin and yang (the harmony of opposing forces and elements). When the free flow of qi is maintained, a person is considered healthy; however, exposure to internal or external pathogens may result in the impairment of qi circulation and the development of disease. Acupuncture involves the insertion of thin, metal needles to stimulate specific points of the body that reach meridians. While the thin needles cause almost no discomfort, they create stimulation that regulates the flow of qi and restores health to the mind and body, thus balancing the yin and yang.