Gender assignment in the newborn with ambiguous genitalia poses a dilemma for the parents and physician, even if the infant has a normal 46XX or 46XY karyotype. In general, female pseudohermaphrodites are reared as female subjects, since they can undergo reconstruction to appear as phenotypic female subjects and they may even be able to bear children. Male pseudohermaphrodites, patients with mixed gonadal dysgenesis and male patients with a micropenis may not be so straightforward, and proper gender assignment in these infants may be difficult. A unified surgical approach to early reconstruction of the external genitalia in these patients, who are to be reared as female subjects, has been developed. Essential to this perineal reconstruction are phallic reduction and recession in which erectile tissue is removed with preservation of the neurovascular bundles and glans, creation of labia minora from flaps of phallic skin and foreskin, a labioscrotal Y-V plasty to produce normal-appearing labia majora and construction of a neovagina with a perineal flap. If the patient is a male pseudohermaphrodite or an infant with a micropenis creation of the vagina is deferred until late adolescence or young adulthood. In other patients in whom the vagina enters the urethra or urogenital sinus proximal to the external sphincter a pullthrough vaginoplasty is performed when the child is 2 to 3 years old. If the vaginal entry is distal to the external urinary sphincter a flap vaginoplasty is performed at the same time as the phallic reduction, and creation of the labia minora and labia majora during infancy. Ten patients (4 with the adrenogenital syndrome, 2 male pseudohermaphrodites, 2 genetic male patients with a micropenis, 1 with mixed gonadal dysgenesis and 1 true hermaphrodite) have undergone reconstruction with this composite procedure. All 10 patients have had a successful cosmetic and early functional result.