Although the renal allograft represents only a single functioning kidney, it lends itself readily to biopsy from a percutaneous approach. Previous contraindications to percutaneous biopsy of a single normally situated kidney do not apply to the renal allograft because of its altered extraperitoneal and superficial location. The transplant operative note and palpation serve to adequately localize the kidney without the need of fluoroscopy, metal tagging or other X ray techniques. The cortex may be safely approached through a perpendicular plane directed toward the lower pole or a tangential plane directed toward the lateral curvature of the allograft. The fibrous capsule's resistance to the needle passage helps localize the periphery of the kidney. Hemostasis is augmented through manual pressure and subsequent pressure dressing. The technique was used in 62 renal biopsies in 62 different patients. Adequate material for microscopic and bacteriologic evaluation was obtained in all cases. There were three episodes of gross hematuria, but no prolonged bleeding, significant perirenal hematoma formation, infection or decreasing renal function after the biopsy procedure.