To define the immediate and long-term volumetric reduction following complete decongestive physiotherapy (CDP) for lymphedema. Design: Prospective study of consecutively treated patients. Setting: Freestanding outpatient referral centers. Patients: Two hundred ninety-nine patients referred for evaluation of lymphedema of the upper (2% primary, 98% secondary) or lower (61.3% primary, 38.7% secondary) extremities were treated with CDP for an average duration of 15.7 days. Lymphedema reduction was measured following completion of treatment and at 6-and 12-month follow-up visits. Intervention: Complete decongestive physiotherapy is a 2-phase noninvasive therapeutic regimen. The first phase consists of manual lymphatic massage, multilayered inelastic compression bandaging, remedial exercises, and meticulous skin care. Phase 2 focuses on self-care by means of daytime elastic sleeve or stocking compression, nocturnal wrapping, and continued exercises. Main Outcome Measures: Average limb volumes in milliliters were calculated prior to treatment, at the end of phase 1, and at 6-to 12-month intervals during phase 2 to assess percent volume reduction. Results: Lymphedema reduction averaged 59.1% after upper-extremity CDP and 67.7% after lower-extremity treatment. With an average follow-up of 9 months, this improvement was maintained in compliant patients (86%) at 90% of the initial reduction for upper extremities and lower extremities. Noncompliant patients lost a part (33%) of their initial reduction. The incidence of infections decreased from 1.10 infections per patient per year to 0.65 infections per patient per year after a complete course of CDP. Conclusions: Complete decongestive physiotherapy is a highly effective treatment for both primary and secondary lymphedema. The initial reductions in volume achieved are maintained in the majority of the treated patients. These patients typically report a significant recovery from their previous cosmetic and functional impairments, and also from the psychosocial limitations they experienced from a physical stigma they felt was often trivialized by the medical and payor communities.