Learning Objectives: 1) Understand the ultrasound features that differentiate significant from insignificant hyperechoic liver masses. 2) Learn the differential diagnosis of nonhyperechoic liver lesions and understand how to guide further work-up when the sonographic findings are nonspecific. 3) Understand the gray-scale and Doppler US findings in normal patients and patients with chronic liver disease. Disclosure: (J.W.C. benefited from a small grant to Mayo from RITA.)