Government-to-Government (abbreviated G2G) is the online non-commercial interaction between Government organisations, departments, and authorities and other Government organisations, departments, and authorities. Its use is common in the UK, along with G2C, the online non-commercial interaction of local and central Government and private individuals, and G2B the online non-commercial interaction of local and central Government and the commercial business sector.
G2G systems generally come in one of two types:
Internal facing - joining up a single Governments departments, agencies, organisations and authorities - examples include the integration aspect of the Government Gateway, and the UK NHS Connecting for Health Data SPINE.
External facing - joining up multiple Governments IS systems - an example would include the integration aspect of the Schengen Information System (SIS), developed to meet the requirements of the Schengen Agreement.