Sonography is a useful modality in the diagnosis of a wide variety of knee disorders, including lesions of the articular cartilage, tendons and ligaments, menisci, synovial space, and adjacent vessels and muscles. Sonography is noninvasive, rapidly performed, widely available, readily accepted by patients, uses no ionizing radiation, and is relatively inexpensive compared to other conventional imaging studies of the menisci, making it a potentially attractive screening examination for knee injuries. Although it is difficult to state the exact place of sonography in the diagnostic workup of knee disorders, we feel that sonography is vastly underutilized. With additional refinements in ultrasound technology and scanning techniques, we expect further expansion of its role in the evaluation of the knee.