Acupuncture is a form of natural healing where one manipulates energy (Ki or Qi), blood and fluids within the body. When disease is upon us there will be stagnation, deficiency or excess of these qualities.
The acupuncturist will then awaken one's own immune system by inserting very fine needles into acupuncture points along energy pathways or channels. There are many ways to manipulate these points and one does not have to use needles. It can be done though fingers (acupressure), and burning herbs (moxibustion).
The acupuncturist can restore or maintain balance by using over 3000 years of refined Chinese, Japanese and Korean traditional medical theories. Part of those theories are an understanding of the duality of who we are (Yin and Yang), the elements that make up our existence (five elements), the inter connectedness between each organ and system, and treating the root cause of illness not just the symptoms.
There are a wide variety of treatment styles and theories, so one must find an acupuncturist who they can relate to and whose techniques are more to their liking. For example most Chinese trained acupuncturists will use strong stimulation to resolve disharmony, where the Japanese trained acupuncturist will use a more subtle approach. All types work, it is a matter of finding what you are comfortable with, or finding an acupuncturist who has diversified in their training and can appease all levels of sensitivities.
If you are reading this now, I believe you may have found one.