To the Editor:— The necessity of obtaining a satisfactory renal biopsy frequently confronts the internist and urologist. At the Massachusetts General Hospital requests for renal biopsy have been frequent because of a study conducted by Richard Field, MD,4in juvenile diabetics with retinopathy who are under consideration for pituitary stalk section. Initially in this study percutaneous needle biopsy of the kidney was performed. Tissue was not obtained from approximately 25% of the patients. In addition, the complications of bleeding, ie, colic due to the passage of clot, and perinephric hematoma requiring drainage appeared with sufficient frequency to demand reappraisal of biopsy techniques. After due consideration, open renal biopsy was instituted. This has now been done in 95 patients. The surgical approach has been standardized, the complication rate negligible, and renal tissue always obtained. Surgical Technique:— Kidney position, the presence of a solitary kidney, or other gross abnormality is determined