Abstract Purpose Cadaveric kidneys from pediatric donors represent an important resource for human allotransplantation. We report 7 cases in which a new technique was used for en bloc transplantation of pediatric cadaver kidneys into adult recipients. Materials and Methods Paired cadaveric kidneys obtained from donors younger than 6 years (mean age 26 months) were transplanted en bloc into 2 children (mean age 12.5 years) and 5 adults (mean age 50 years) using en bloc extraperitoneal interposition of the donor aorta and vena cava into the recipient external iliac artery and vein. Results All patients had excellent perfusion immediately following transplantation on 99m technetium-pentetic acid perfusion scans. Serum creatinine decreased to its nadir an average of 7 days post-transplantation in all but 1 patient. In 3 patients glomerular filtration rate increased 3 to 5-fold at 3 months and 6 months after transplantation. No patient had venous or arterial thrombosis postoperatively and 2 had ureteral leaks. In 3 patients moderate to severe biopsy proved acute rejection episodes were successfully reversed by intensifying immunosuppressive treatment and recovery of allograft function was excellent following antirejection therapy. Grafts were lost due to chronic rejection at 10 years in 1 patient and noncompliance in 1. Currently 5 patients are well with normal serum creatinine values at 3 months to 1 year of followup. Conclusions En bloc transplantation of small pediatric kidneys using a new technique averts the complication of vascular thrombosis and provides adequate mass to achieve a normal level of renal function.