The Information Technology Strategies Implementation Group exchange Document Type Definition (the ITSIG exchange DTD) has been designed for use within the ISO system for the development and publication of standards and other ISO delivrables. It was recognized by ITSIG that it is not practical to provide a single DTD for all standards needs for all participants within the ISO system. Rather it was decided to have a “common” DTD for the exchange of standards between the different partners to permit each partner to map between the exchange DTD and their own “in-house” DTDs, i.e. variants of the base DTD. (By preference, differences between the exchange DTD and the individual variations should, however, be minimized. Equivalent transformations of DTD fragments will help to overcome software limitations.) The ITSIG exchange DTD is compliant with the requirements of the ISO/IEC Directives, Part 2. Documents prepared in SGML format shall be conformant with the ITSIG exchange DTD.

The SGML group of ITSIG is responsible for the maintenance of the ITSIG exchange DTD.