Manual lymphatic drainage was pioneered by Danish Drs. Emil Vodder and Estrid Vodder in the 1930s for the treatment of chronic sinusitisand other immune disorders. While working on the French Riviera treating patients with chronic colds, the Vodders noticed these patients hadswollen lymph nodes. In the 1930s, it was considered taboo to tamper with the lymphatic system due to the medical profession's poor understanding of this system. The Vodders were not deterred by this and, in 1932, began to study the lymph system, developing light, rhythmic hand movements to promote lymph movement. In 1936, they introduced this technique in Paris, France, and after World War II, they returned to Copenhagen to teach other practitioners to use this therapy.