The kidneys are organs whose function is essential to maintain life. Most people are born with two kidneys, located on either side of the spine, behind the abdominal organs and below the rib cage. The kidneys perform several major functions to keep the body healthy. Filtration of the blood to remove waste products from normal body functions, passing the waste from the body as urine, and returning water and chemicals back to the body as necessary. Regulation of the blood pressure by releasing several hormones. Stimulation of production of red blood cells by releasing the hormone erythropoietin. The normal anatomy of the kidneys involves two kidney bean shaped organs that produce urine. Urine is then carried to the bladder by way of the ureters. The bladder serves as a storehouse for the urine. When the body senses that the bladder is full, the urine is excreted from the bladder through the urethra. Kidney Disease When the kidneys stop working, renal failure occurs. If this renal failure continues (chronically), end-stage renal disease results, with the accumulation of toxic waste products in the body. In this case, either dialysis or transplantation is required.