Nonoperative ablation of the testicular artery has been described in animals using the Burdizzo clamp, but not in humans. We report a case of incisionless castration performed using local anesthesia, in a transsexual who wished to avoid the pain, expense, and scar associated with the open procedure. The Burdizzo clamp crushed the spermatic cord bilaterally, and the testis was allowed to atrophy. The soft-tissue damage was minimal, and the serum testosterone fell to castrate levels. This method has proved useful for castration in a transgender patient, but could also be used for castration in patients with advanced prostate cancer.