Thirteen patients with secondary obstructive lymphedema of the upper and lower extremities were treated by microlymphaticovenous anastomosis. The immediate and long-term results have been very satisfactory. An average reduction in the circumference of the affected limb of 6.2 cm was obtained, and subjective symptoms and objective signs were improved. No correlation was established between the quality of the results and the duration of the lymphedema or the number of anastomoses employed in treating it. On the basis of microlymphaticovenous surgery for lymphedema of the extremities, the authors also developed a microlymphaticovenous procedure to treat lymphedema of the external genitalia and applied it clinically in two patients. Good results were obtained in both instances. The operative techniques and four case histories are described, and the advantages of microlymphaticovenous anastomosis, the selection of patients, and the facts required for success of the surgery are discussed.