Sharing and communicating information is a fundamental task in modern medicine. The health care system of the western world is based on teamwork of professionals who participate in the care of patients. Exchange of information (not just data) requires the communicating parties to agree on a communication channel, an exchange protocol, and a common language. The language includes an alphabet,
... [Show full abstract] words, phrases, and symbols that express and assign meaning, understood by all. The most common forms of communication are the spoken word and the paper-based patient record. Computers and communication systems improve the sharing of health care information by overcoming the limitations imposed by the dimensions of time and location. However, natural language is still too complex and too ambiguous for current computing devices to handle the complex interactions between health care professional and patients. A simpler 'language' is needed that uses domain specific vocabularies (and/or codes), well-defined exchange protocols for data, information, knowledge, and, in the future, perhaps even wisdom. This simpler 'language' is expected to handle most of the routine information exchange but not eliminate natural language. It is essential that health care information systems preserve and incorporate natural language expressions and integrate them with structured vocabularies. Today, agreeing on standard data exchange protocols and domain specific vocabularies and codes is our greatest challenge. However, standards alone are not sufficient. Acceptance of the standards by the health care professionals, verifications in clinical environments, and implementation agreements by the medical informatics industry are essential. The group on 'Sharing and Communication of Health Care Information' addressed the issues raised above and unanimously recommends a number of steps that will improve the sharing of information. In addition, specific recommendations are offered to governments, health care institutions, and to developers of health care information systems.