The authors have succeeded in passing the fiberscope up to the kidney by the transurethral procedure and taking photographs and movies of renal calyx, pelvis and ureter for the first time in the world. Our long cultivated dream on pyeloureteroscope has come true. When these improvements, which the authors just mentioned, have been achieved and an ideal pyeloureteroscope has been accomplished, tiny lesions of kidney, which have not been diagnosed by the current clinical methods, would be discovered in the early stage of the disease. In the future, this fiberscope would be so equipped with accessory apparatuses that it could be used for the minor treatment or biopsy of the lesions in the upper urinary tract. Therefore, the authors believe the fiberscope would contribute tremendously to the progress of medicine and happiness of mankind.