The use of broad band transducers determined a great increase in spatial, contrast and vascular resolution of ultrasound probes dedicated to breast studies. Providing better definition of normal as well as pathologic features, high resolution sonography improves the specificity of the diagnosis for the majority of malignant nodules and allows a better definition of both local and regional staging. The most impressive results have been achieved in the evaluation of multifocal and multicentric carcinomas, in determining the size of the tumor, its degree of invasion of the surrounding tissues and of the ducts. Color and power Doppler offer further characterization that may be particularly useful in evaluating tumor vascularity during therapies that are planned before surgery. These new staging possibilities must push the radiologists to adequate their instruments and their methods to provide up-to-date and more accurate informations to the surgeon.