Ultrasonography is the first choice for screening patients with suspected liver lesions. However, due to lack of contrast agents, ultrasonography is less sensitive and specific compared with computed tomography and magnetic resonance imaging. The advent of microbubble contrast agents increases both sensitivity and specificity dramatically. Real-time evaluation of the vascular phase can currently be achieved by combining new microbubble specific methods with second-generation contrast agents. The enhancement pattern in the vascular phase, combined with the behavior in the liver-specific late phase, allows the characterization of the most frequent focal liver lesions, with an accuracy similar to those of dynamic computed tomography and magnetic resonance imaging.