Ultrasound (US) evaluation of the urinary tract in nephrological settings provides the right assessment of many clinical pictures. Actually it allows a realtime differentiation between parenchymal lesions, obstructions or tumoral masses. On the contrary the differential diagnosis of parenchymal nephropathies appears more difficult due to the fact that different histological pictures may present similar ultrasound findings. The echo-color-Doppler is a valid integration of the conventional US B-mode technique thanks to the measurement of some indirect parameters such as the resistance index (RI) and the pulsatility index (PA). It has been showed that the IR results higher in patients with tubulo- interstitial or vascular nephropathies than in those with glomerular ones. It is still debated the relationship between IR and the progression of the renal damage. In the recent years the RIs have gained importance as vascular compliance surrogates: actually their rise has been observed both in cases of vascular damages and in systemic atherosclerosis or associated with other features of renal damage. More studies based on sophisticated US techniques are warranted in order to make the US as golden standard for the diagnosis of parenchymal nephropathies.