Manual Lymph Drainage (MLD) is a technique which is used for swelling or edema. There are different levels of training for the use of this technique. For example, many massage therapy students will learn the basic education and skill for the treatment of swelling or edema due to injury such as a sprained ankle. Specialized training is needed for the treatment of swelling or edema where the lymph nodes or vessels have been damaged, destroyed, removed or reduced from birth. One such condition is the treatment of lymphedema, which is swelling that, will not go away, a result of lymph nodes or vessels being damaged from radiation or removed during cancer surgery. Massage Therapists are one of the professions that may obtain this training. There are different training facilities available to learn this technique, but the Dr. Vodder School International has the most extensive training available and exceeds the Lymphology Association of North America (LANA) requirements. There are 4 levels of training each lasting 5 days for a total of 160 hours of classroom education. If a therapist has the Dr. Vodder Certification for MLD, they must attend refresher courses every 2 years to maintain their credentials with the school. This ensures that the techniques provided by the therapist are constantly being monitored and corrected to provide the most effective treatment results.