Progress in pathology is related to application of new biological techniques and impact of electronic devices affecting transfer of information and images. The increase of specification of all kinds of disease classification induces a specific need for data exchange and expert consultation. The momentary technical situation in communication lines connected with medical fields, especially pathology is characterized by parallel operation of two basically different communication systems, namely a) systems based upon computerized data exchange (E-mail, etc.), and b) systems working at public access, i.e. telephone lines and their successors (digitized network, satellite system). Practical use in telecommunication in pathology has been gathered nearly exclusively by use of the second (public) system, and includes intraoperative classification of histological images (frozen sections), expert consultations, panel discussions, quantitative measurements, and access to image data bank systems. The use of remote control microscopes has been reported to work without major errors from Norway and Switzerland. In Norway, images and diagnostic informations are transferred by use of broad band networks (satellite communication), whereas in Switzerland the digitized network ISDN is used. The experiences show clearly that remote control microscopes are practicable and reliable tools for daily diagnostic work of pathologists, and that the quality of the transferred images is sufficient to allow sophisticated diagnoses. Expert consultations are routinely performed by use of the common telephone network in lung pathology, and can not be underestimated in their impact on the daily work. Accuracy of diagnosis, quality of staining and tissue handling, and reliability of diagnosis are automatically improved besides the positive legal aspects.