The development of highly efficient imaging systems has essentially improved the chance of diagnosis. This has limited the indication of invasive examinations. In the individual case the widespread possibilities of diagnostic procedures require critical choice of adequate methods. Strict criteria should be taken into consideration. If efficiency is comparable, the method with lower risks and costs should be preferred. New methods low in risk can replace certain conventional x-ray examinations. Referring to this, especially the examination of the kidneys and the urinary tract is concerned. Technical development has achieved remarkable progress also on the area of conventional x-ray examination. Besides the improvement of diagnostics, the radiation dose has been reduced considerably. After all, the quality of examination is essentially influenced by the examinator's experience.