The International Lattice Data Grid (ILDG) was started in 2002 by research groups around the world, including the US, UK, Japan, Germany, Italy, France, and Australia, with the aim of making the basic data sets from Lattice QCD simulations available to the international scientific community.

The data sets stored in ILDG are ensembles of gauge field configurations. They consist of a set of metadata and binary files. The metadata is available as XML documents which conform to the XML schema developed by the ILDG metadata working group. The metadata is searchable via the metadata catalogue (MDC) web service.

ILDG has defined standardized metadata and data formats, as well as interfaces to data access services by using Grid technologies to enable a number of widely distributed data repositories (organized within regional grids) to function as a global federated data repository.