Gonadal distribution in 409 cases of human true hermaphroditism is reviewed. An ovary was found on the left side of the body in 62.8% of the cases and the testis on the right side in 59.5%. The ovotestis is the most common gonad of the true hermaphrodite; amongst 806 gonads in 406 cases it was found in 44.3%. In this paper we give a detailed description of the morphology of ovotestis, testis and ovary in the true hermaphrodite. In addition we discuss the effects of fetal androgens and Müllerian inhibiting factor on the Wolffian and Müllerian ducts. Correlations between chromosomal complement and gonadal distribution are presented. True hermaphrodites with a 46,XX karyotype most commonly have an ovary on one side and an ovotestis on the other side; those with a Y-chromosome have a testis in 61% of cases. An analysis of the ratio of ovarian and testicular tissue within ovotestes showed a continuum from very little ovarian tissue to a small portion of testicular tissue. Each type of tissue was clearly demarcated. Hypotheses for gonadal induction in the true hermaphrodite should take cognizance of these facts. True hermaphrodites with a 46,XX chromosomal complement were characterized by a male phenotype in 54% of cases. This group may suggest a greater testicular induction ability in the genome as compared to the 46% with a female phenotype.