Technological advances in ultrasound, computed tomography (CT), and magnetic resonance (MR) imaging over the past decade have allowed radiologists to noninvasively characterize liver masses. Each imaging modality offers unique and valuable information that aids in the differential diagnosis of a hepatic mass. The vascularity of hepatic masses and their relationship to adjacent hepatic vasculature can be beautifully depicted with color and power doppler ultrasound. Multidetector helical CT has allowed tumor characterization during multiple vascular phases of contrast enhancement. New rapid MR sequences allow images of the liver to be obtained without motion artifact. Hepatocyte-specific MR contrast agents permit unique tumor charaterization. This article reviews the clinical, pathologic, and imaging appearances of primary hepatic malignancies with an emphasis on multi-modality approach to tumor characterization.