Review of John Colapinto’s As Nature Made Him. One of two twin infants in Winnipeg loses his penis as a result of a surgical mishap during their circumcision. His parents follow the advice of a controversial sex researcher and, with the aid of surgical castration and “a rigid programme of social, mental and hormonal conditioning,” raise him as a girl, in what is called “the first infant sex reassignment to be reported on a developmentally normal child.” The case “made medical history and was lauded as completely successful.” It was anything but.