The ADS catalogue holds the digital archives of a huge number of archaeological interventions from the UK and beyond in around 400 collections, these range from the outputs of single excavations to large scale developer funded projects encompassing hundreds of individual archaeological interventions. As well as digital archives and fieldwork outputs the catalogue contains a number of scholarly resources intended specifically as reference sources for further research on topics such as lithics, ceramics and animal bone. The catalogue also contains digitised (or born digital) versions of various significant journals and series running to many thousands of individual articles. These include scholarly journals such as the Proceedings of the Society of Antiquaries of Scotland, Research Reports from the CBA and around 8000 'grey literature' fieldwork reports. In addition to the catalogue holdings the ADS provides access to over 1,000,000 aggregated resource discovery metadata records for monument inventories from around the UK (including data from the RCAHMS, English Heritage and numerous local authorities). The ADS also hosts both the Archaeological Records of Europe Networked Access (ARENA2) service which aggregates monument inventory data from a number of European partners and the Transatlantic Archaeology Gateway portal allowing cross-searching with archives held in tDAR at Digital Antiquity, Arizona State University, ARENA is currently being both geographically expanded and technically enhanced.