Access to Memory - almost always written AtoM - is an open-source, web-based application for describing, managing and publishing archival holdings. It was originally developed with the International Council on Archives (ICA) to make standards-based description available to institutions of any size, anywhere in the world. Because it runs in the browser and stores everything in a relational database, a single AtoM instance can serve a reading-room catalogue, a public discovery portal and an internal cataloguing workbench at once.

What distinguishes AtoM from a generic content system is that its data model is built directly on the descriptive standards of the archival profession. You are not bending a blog engine to hold finding aids; you are working in software that already understands fonds, series and items, creators, and the difference between a record and its context.

Standards baked into the model

AtoM ships with templates that implement the ICA descriptive standards natively, so your data is portable and interoperable from day one:

  • ISAD(G) for multilevel archival description of records.
  • ISAAR(CPF) for authority records describing corporate bodies, persons and families (creators).
  • ISDIAH for describing the repositories that hold the records, and ISDF for functions.
  • Import and export in EAD 2002 and EAC-CPF XML, plus Dublin Core and MODS for lightweight interchange and OAI-PMH harvesting.

Where AtoM fits in the wider ecosystem

AtoM is a description and access layer, not a digital preservation repository. In an OAIS-aligned workflow it typically pairs with a preservation system (for example one that produces PREMIS preservation metadata and manages fixity), which pushes descriptive information and access copies to AtoM for public discovery. Understanding this boundary - access here, preservation elsewhere - prevents the common mistake of treating the catalogue as a safe store for master files.

In practice. Before you catalogue a single record, decide which template your institution will standardise on - most archives choose ISAD(G) for records and ISAAR(CPF) for creators. Consistency in template choice is what later makes clean EAD export, aggregation into national portals, and reliable search behaviour possible.

Key takeaways

  • AtoM is an open-source, browser-based tool for standards-based archival description and public access.
  • Its data model implements ICA standards directly - ISAD(G), ISAAR(CPF), ISDIAH, ISDF - and exports EAD and EAC-CPF.
  • It handles description and access, not preservation; pair it with an OAIS/PREMIS-aware repository for master files.

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Last modified: Saturday, 1 August 2026, 11:03 AM