Acupuncture is inserting one or more acupuncture needles at specific points to stimulate and regulate the Qi (energy) flow and to restore the Yin/Yang balance in a human body. The fundamental premise of Traditional Chinese Medicine (TCM) says that there is an energy or Qi flowing through the meridians or energy channels within human body. Any blockage of the flow will disturb the dynamic energetic balance and may lead to the development of disease

NIH Consensus Conference:

Acupuncture is a component of the health care system of China that can be traced back for at least 2500 years. The general theory of acupuncture is based on the premise that there are patterns of energy flow (Qi) through the body that are essential to health. Disruptions of this flow are believed to be responsible for disease. Acupuncture may correct imbalances of flow at identifiable points close to the skin.