Telemedicine is likely to adopt rather than create most of its protocols and standards as it becomes an integral part of medical practice. To optimize this process, it will be necessary to understand how to use existing protocols and standards, and influence the development, evaluation, and modification of new ones. We have identified key participants in standards setting activities under the titles of international government, United States government, professional certifying organizations, and independent institutes. We have reviewed their roles in establishing standards for identification of patients and providers, content and structure of patient records, terminology and codes of medical information and records, and transfer of messages and data. We have addressed requirements for storing and viewing images, the impact of image resolution on accuracy of clinical interpretation, the choice of communications protocols to satisfy transmission requirements, the need to link images and text data, and the evaluation of telemedicine systems.