Manual lymphatic drainage (MLD) is a type of gentle hands-on therapy which is intended to encourage the natural drainage of lymph fluid, which carries waste products away from the tissues back toward the circulatory system to eventually be processed out of the body in via the kidneys. The lymphatic system has no pump, instead it depends on small, infrequent contractions of the smooth muscle cells in the walls of lymph vessels and the movement of skeletal muscles to move lymph through the vessels. Manual lymph drainage uses a specific amount of pressure (less than 9 ounces per square inch) and rhythmic circular movements to stimulate lymph flow and is generally a very pleasant and relaxing therapy.