"The Integrated Public Sector Vocabulary (IPSV) is an 'encoding scheme' for populating the e-GMS Subject element of metadata. It is fully compliant with ISO 2788 and BS 8723, the International and British Standards for monolingual thesauri. The vocabulary was developed with the backing of the ODPM (Office of the Deputy Prime Minister) and the eGU (Cabinet Office e-Government Unit). Version 1.00 was released in April 2005; Version 2.00 supersedes it, as of 3 April 2006.
Version 1 was developed by merging three earlier lists: the GCL (Government Category List), LGCL (Local Government Category List) and seamlessUK taxonomy. It had 2732 preferred terms and 4230 non-preferred. Version 2 is much bigger, with 3080 preferred terms and 4843 non-preferred. As a result, IPSV now covers internal-facing as well as public-oriented topics. You can still refer back to the superseded version if necessary. IPSV is just one of a family of lists you can obtain from the esd-standards site.
Two subsets of IPSV are now available:
The Internal Vocabulary covers only the 'internal-facing' topics. It has 756 preferred terms and 1333 non-preferred.
The Abridged version covers the whole scope of IPSV but is limited to the upper levels. It has 549 preferred terms and 1472 non-preferred."