The AGS format is a digital data interchange format for the geotechnical community, consisting of a data dictionary, rules and the file format itself. The Association of Geotechnical and Geoenvironmental Specialists (AGS) in the UK set up a Working Party in 1991 to reduce the proliferation of data formats and establish a format to transfer data between systems. The AGS Format was first published in 1991 and has been updated and extended in response to industry requirements ever since. AGS3.1 which was published in Dec 2004 contains monitoring and instrumentation data. The latest version AGS4.0 contains a significant range of additional fields to cover the requirements of EC7, mainly for QA/QC purposes and has added a totally reworked environmental section. The AGS Format continues with an ASCII commas and quotes format although other file types have been studied and are being investigated for future versions. The format has been adopted world wide in the practising construction industry for Australasia, China and Singapore in the Far East, through India and the Gulf States in the Middle East, Eastern and Western Europe and is beginning to be used in the USA. The paper will discuss the origins of the format, its maintenance and continued changes and in particular the methodology used for governance and development.