Telepathology is the practice of pathology over a long distance. Components of a telepathology system include the following: a remote-controlled light microscope attached to a high-resolution video camera; a pathologist workstation incorporating controls for manipulating the microscope and a high-resolution video monitor; and a telecommunications linkage. An immediate challenge is to establish the specifications for a telepathology system. Breast tissue has served as a model. Receiver operator characteristic curve studies show that the pathologist’s ability to discriminate benign from malignant breast tumors is similar using either a conventional light microscope or a video monitor with approximately 1000 lines of resolution.