Thirty-eight girls with malignant ovarian tumors were reviewed and studied during a 43-year period, 1945 to 1988 inclusive. The age range was 3 to 16 years. Eighteen girls were prepubertal and 16 were pubertal at diagnosis. Precocious puberty was noted in 4 children. The most common presenting symptoms and signs were pain, abdominal swelling, and pelvic mass. Emergency surgery for acute pain (? appendicitis) was needed in only 7 patients. Tumor size and cysts did not relate to histology or outcome. Tumors were classified histologically (germ cell, sex cord/stromal, epithelial tumors). Twenty-one (54%) of the patients survived 1 to 27 years (median, 8 years). Sixteen were left with ovarian tissue, 11 functioning. Diagnosis and treatment have been aided by better noninvasive radiological methods, tumor markers, newer and better chemotherapy, and pathological review and reclassification of these tumors as pediatric experience slowly increases. We can make at least four statements that differ from our past experience: (1) pure endodermal sinus tumor was previously confused histologically with embryonal carcinoma; (2) gonadoblastoma is associated with 45,X/46,Y, 45,X, or 46,Y karyotype and is known to be premalignant; (3) sex cord/stromal tumors are not necessarily malignant and metastatic behavior cannot be predicted from the histology; and (4) currently, epithelial tumors are classified as cystadenomas and are considered to be borderline malignancy. Current management should aim at both cure and preservation of fertility with conservative surgery whenever possible. The future must lie in chemotherapy.