Abstract : Ada is the result of a collective effort to design a common language for programming large scale and real-time systems. This report is the proposed standard document for Ada. Since the early 70's, DoD has been committed to the use of High Order Languages and has developed an extensive set of requirements for a single language which could be adopted for use throughout DoD. In April 1978, the language designed by Jean Ichbiah and his team at Honeywell/Cii- Honeywell Bull, Paris, France, was chosen to be the new DoD language. For the ensuing fourteen months, Ada was subjected to an intense period of test and evaluation by the international computer science community and the design was modified in response to language issues raised during the test and evaluation. It will be added to the list of approved languages for use in DoD systems and promises to have a significant impact on DoD software development. Ada will be reviewed under American National Standards Institute (ANSI) canvass procedures for designation as an American National Standard and is on the agenda for the International Standards Organization (ISO). The DoD is concentrating on the development of compilers and an integrated programming support environment for Ada software. Although developed for use in DoD systems, Ada has generated considerable interest in the international computing community, particularly NATO, as well as in the U.S. commercial computing community.