Complementary techniques to laparotomy are required to monitor patients with lymphomas both before and after treatment. Our preliminary experience with grey-scale ultrasonography is presented. Fifty-two patients, themajority with Hodgkin's disease or other lymphomas, were examined with ultrasound equipment which was custom built. The essential difference between grey-scale equipment and conventional machines is the ability to display the internal consistency of soft organs. Of 20 spleens examined prior to splenectomy, the ultrasonic scan was considered suggestive of involvement in seven of nine that showed histological evidence of Hodgkin's disease. Threeof 11 histologically negative spleens were considered to be positive preoperatively and two of nine read as negative on the scan contained histological disease. Fifty livers were examined with ultrasound. Of seven patients with histological involvement four were read as positive and three as negative and six of 43 patients with no macroscopic or microscopic evidence of liver infiltration were also considered to have a positive ultrasonic scan. Ultrasonic scanning has proved useful for demonstrating enlarged lymph nodes in the porta hepatis, upper para-aortic lymph nodes and bulky mesenteric nodes. On the basis of these preliminary observations the potential value and application of the technique is discussed.