Health Level Seven is one of several ANSI-accredited Standards Developing Organizations (SDOs) operating in the healthcare arena. The HL7 Organization was founded at the University of Pennsylvania in 1987 to design a consensus-based standard for the electronic exchange of healthcare-related information. Interest in a standard arose because hospitals had seen a dramatic rise in the computerization of ancillary departments requiring integration with existing billing, laboratory, and patient-care systems.

Most SDOs produce standards (sometimes called specifications or protocols) for a particular healthcare domain such as pharmacy, medical devices, imaging or insurance (claims processing) transactions. Health Level Seven’s domain is clinical and administrative data. Headquartered in Ann Arbor, MI, Health Level Seven is like most of the other SDOs in that it is a not-for-profit volunteer organization. Its members; providers, vendors, consultants, government groups and others who have an interest in the development and advancement of clinical and administrative standards for healthcare, develop the standards. Like all ANSI-accredited SDOs, Health Level Seven adheres to a strict and well-defined set of operating procedures that ensures consensus, openness and balance of interest. The term “Level Seven” refers to the seventh (or highest) level of the Open Systems Interconnection (OSI) model of the International Standards Organization (ISO), which is called the Application Layer. While HL7 does not require a specific set of network protocols, it does assume an existing network connection supplying the lower six layers of the network. HL7 specifies only the abstract message of Layer Seven. Layer Seven, also called the application layer, is responsible for specifying the information transfer between two network applications.

HL7 encourages the creation of flexible, cost-effective approaches, standards, guidelines, methodologies, and related services for the interoperability between healthcare information systems. HL7 provides a forum for the effective and efficient communication between the constituents of the healthcare community as represented by its membership, which consists of an international community of healthcare organizations, vendors, developers of healthcare information systems, consultants and systems integrators, related public and private healthcare services agencies. International affiliates are independent entities whose mission is to advance the acceptance and usage of HL7 on a worldwide basis, including the internationalization of the HL7 data exchange standards. HL7 India is one such international affiliate which co ordinates the activities of HL7 in India.