NISO Announces Publication of Updated Standard on Criteria for Indexes (ANSI/NISO Z39.4)

The National Information Standards Organization (NISO) announces today the publication of its updated ANSI/NISO Z39.4, Criteria for Indexes, incorporating feedback from the public comment period earlier this year. It replaces the original ANSI/NISO Z39.4 standard (Guidelines for Indexes and Related Information Retrieval Devices), last updated in 1984, and is an updated and expanded version of NISO’s Guidelines for Indexes and Related Information Retrieval Devices (a technical report, TR02-1997).

The updated standard provides guidelines for the content, organization, and presentation of indexes used for the retrieval of information. It deals with the principles of indexing—regardless of the type of material indexed, the indexing method used, the medium of the index, or the method of presentation for searching.

“We are delighted that the ANSI/NISO Z39.4 standard has been updated to cover both print and online publications, including web resources and electronic databases, not to mention accessibility aspects of index output,” said Marti Heyman, Executive Director, Metadata Strategy and Operations at NISO member organization OCLC, and a Co-chair of the Z39.4 Working Group. "Everyone’s ultimate goal is quality. We hope that this will lead to wider adoption and, therefore, better and more consistent end-user experience."

Her fellow Co-chair, Pilar Wyman, Chief Indexer at Wyman Indexing added, “We are grateful to everyone who provided feedback on the draft standard, especially our Working Group members who came from different indexing backgrounds and were able to share their deep knowledge of indexing across various perspectives. As a result, the new Z39.4 standard will be usable by a broad spectrum of organizations, providing a more efficient and effective process and experience for everyone who creates or uses indexes.”

"Many thanks to the Z39.4 Working Group, led by Marti and Pilar, for its hard work updating the technical report. Now “upgraded” to ANSI/NISO standard status, it will better serve the needs of today’s indexers and index users,” said Todd Carpenter, NISO’s Executive Director. “This is a great example of the importance of mobilizing to ensure that our authoritative tools evolve to meet the changing needs of the community—and provide valuable consistency and predictability to enhance published information.”

The NISO Z39.4 standard is available at

About NISO

NISO, based in Baltimore, MD, USA, aims to build knowledge, foster discussion, and advance authoritative standards development through collaboration among the cultural, scholarly, scientific, and professional communities. To fulfill this mission, NISO engages libraries, publishers, information aggregators, and other organizations that support learning, research, and scholarship through the creation, organization, management, and curation of knowledge. NISO works with intersecting communities of interest and across the entire lifecycle of information standards, and is a not-for-profit association accredited by the American National Standards Institute (ANSI). For more information, visit the NISO website ( or contact us at


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Nettie Lagace

Associate Executive Director
Nettie Lagace is the Associate Executive Director at NISO, where she is responsible for facilitating the work of NISO's topic committees and development groups for standards and best practices, and ...