Digital content is evolving quickly, and so are expectations for inclusive access. Libraries are being asked to deliver e-books, audiobooks, and streaming media in ways that work for everyone. But there’s a practical challenge underneath those expectations: accessibility features are only discoverable if the metadata describing them is structured, consistent, and able to travel intact across the full metadata ecosystem.

Over the past two years, particularly as the European Accessibility Act (EAA) has increased attention on accessibility requirements for digital content, we’ve focused on a clear goal: making accessibility metadata reliable, standards-based, and scalable across WorldCat and the systems that feed it.

Here’s what that looks like in practice.

Note: This post is informational and not legal advice. Libraries and organizations should consult appropriate legal guidance regarding accessibility requirements.

Accessibility metadata is a shared responsibility

For electronic resources, accessibility metadata typically originates upstream with publishers and producers who know how a file was created and what features it supports. From there, the information moves through multiple systems and partners: publishers, distributors and aggregators, platforms and vendors, library discovery environments, and shared cataloging ecosystems.

The EAA has reinforced what many already understood: every part of the metadata workflow plays a role in keeping accessibility information flowing. If that information drops out at any stage, or arrives in inconsistent forms, libraries and users pay the price through additional work and reduced discoverability.

Establishing standards that bridge publishing and libraries

A major part of our work has focused on helping accessibility metadata move between publishing systems and library-standard metadata structures without losing meaning along the way.

MARC 341 and 532: core carriers for accessibility metadata

In library metadata, accessibility information is most directly represented in:

• MARC 341 (Accessibility Content)
• MARC 532 (Accessibility Note)

These fields have existed for years but historically saw limited use. As accessibility expectations have increased, especially for digital content, these fields have become essential infrastructure for consistent discovery and access.

A key milestone: adding ONIX vocabulary support to MARC 341

In December 2024, we worked with the Library of Congress to add ONIX accessibility vocabulary support to MARC 341.

This matters because:

• ONIX is the publishing industry’s primary metadata format.
• ONIX includes a rich accessibility vocabulary.
• Supporting ONIX vocabulary in MARC 341 creates a standards-based bridge that helps accessibility metadata move more consistently from publisher feeds into library systems.

This is an important example of cooperative metadata work in practice. Publishers and libraries often describe resources using different metadata standards. Aligning those standards helps accessibility metadata remain interoperable across systems and improves how users discover accessible content.

Carrying accessibility metadata forward in WorldCat

WorldCat is not static. Records are continuously added, matched, deduplicated, enriched, and merged. For accessibility metadata to remain useful, it must persist throughout that full lifecycle.

We mapped and validated how accessibility metadata moves through WorldCat ingest and processing workflows so that when records merge, accessibility metadata carries forward into the resulting record. That means if one record contains strong descriptive metadata and another contains accessibility details, the merged result can preserve both, reducing rework and improving discovery.

Scaling implementation through workflows and enrichment

Standards only matter if they can be implemented consistently across partners, formats, and systems.

ONIX-to-MARC crosswalk enhancements

Our teams expanded ONIX-to-MARC crosswalk workflows to include accessibility metadata.

One challenge is that publishers often describe EPUB and PDF formats separately in ONIX because accessibility features may differ by format, while libraries frequently prefer a single provider-neutral e-book record.

To support both needs, we established repeatable rules to:

• map ONIX accessibility elements into appropriate MARC fields,
• identify related product records,
• consolidate records appropriately,
• preserve meaningful format distinctions so accessibility features remain accurate and usable.

Enriching records at scale using existing metadata signals

Not all accessibility-relevant information arrives neatly structured. Our Metadata Quality teams defined criteria to identify records where accessibility characteristics were already present elsewhere in the metadata and could be safely expressed in MARC 341.

Recently, that work enabled enrichment of approximately 1.2 million records, contributing to significant growth in accessibility metadata across WorldCat.

What this means for libraries and users

This work improves outcomes that matter to libraries:

• more reliable discovery of accessible content,
• less local remediation work for catalogers,
• more consistent metadata across vendors and platforms,
• better user experiences for people trying to identify resources that meet their accessibility needs.

It also reinforces OCLC’s role across the metadata ecosystem. We do not simply receive metadata. We help establish the standards that make metadata interoperable, and we operationalize those standards at global scale.

Ultimately, stronger accessibility metadata helps libraries create discovery experiences that are more inclusive, more reliable, and more usable for the communities they serve.