A prospective randomized study was carried out to investigate whether the addition of manual lymphatic drainage (MLD) to the standard therapy could improve treatment outcome in women with lymphedema of the ipsilateral arm after breast cancer treatment. Forty-two patients were randomly assigned to receive standard therapy or standard therapy plus MLD 8 times in 2 weeks and training in self-massage. The standard therapy consisted of use of a compression garment, exercises and information about lymphedema and skin care. The efficacy of treatment was evaluated by reduction in lymphedema volume during treatment and by improvement in symptoms potentially related to lymphedema. The patients were followed-up for a total of 12 months. The study showed that both groups obtained a significant reduction in edema and that MLD did not contribute significantly to reduce edema volume.