Pelvic lymph accumulation (lymphocele) is a recognized complication of renal transplantation. During a 12-year period 166 renal transplants were performed in 143 children at our institution. From 1973 to 1979, 5 lymphoceles were treated in 64 children. From 1979 until the present a technique of peritoneal fenestration has been performed in 69 children, in whom 1 lymphocele developed. Lymphoceles required surgical treatment in 5 of the remaining 10 cases that were not fenestrated. Our experience with peritoneal fenestration as a method of lymphocele prevention has been excellent, and we recommend it as a prophylactic addition to renal transplant surgery.