This Chapter is a dialogue from the Yellow Emperor's Classic of Internal Medicine, specifically Chapter 12, exploring the relationship between the twelve meridians and twelve bodies of water. Qibo, answering the Yellow Emperor's questions, explains the correspondence between the meridians, internal organs (zang and fu), and water systems, emphasizing the importance of balance and proper acupuncture techniques. He details specific needle depths and retention times for different meridians, based on their qi and blood characteristics and the patient's physique. Ultimately, the text advocates for a holistic approach to acupuncture, considering individual variation and adapting treatment accordingly.