HL7 Version 2

HL7 Version 2 (a.k.a. Version 2 or V2) is a HL7 messaging standard intended to support workflows within hospital organizations.

The standard was initially created in 1987. Since then various 2.x versions have been published (2.0 up to 2.6 -as of 2006). The various subversions are Backwards Compatible. The current version consists of 16 chapters, each covering a different area of functionality. The default encoding syntax of V2 (its ITS) is based on a delimited format; there is also an alternative XML-based syntax specification.

Messaging standards are particularly important because they define how information is packaged and communicated from one party to another. Such standards set the language, structure and data types required for seamless integration from one system to another.

Currently, HL7 version 2 is supported by every major medical information systems vendor in the United States.