AbstractThe pelvis of the infant and child has different anatomic relationships than the adolescent or adult pelvis, and the knowledge of congenital anomalies of the rectum and bladder can assist in treating the primary neoplasms of the pelvis. The most common neoplasms are rhabdomyosarcomas of the bladder, prostate, and vagina; sacrococcygeal teratoma; and the germ cell tumors, including teratomas, endodermal sinus tumors, and the choriocarcinomas. Rapidly improving chemotherapy for all of these lesions has resulted in a changed role for the surgeon. Less radical resection of these tumors is being performed whereas it is necessary to have more precise histologic and genetic identification of the tumor and the specific anatomic location and extent of the tumor in the pelvis. Survival for all types of childhood pelvic neoplasms has improved dramatically under the influence of the combined children's cancer study groups, which have been functioning for the last 20 years. Because of the complexities of diagnosis and treatment of these pelvic neoplasms in childhood and because the survival rates have dramatically improved with the most current therapy, these children should be cared for in a children's center that is part of the major children's cancer study groups. J. Surg. Oncol. 2001; 77:65–71. © 2001 Wiley‐Liss, Inc.