Standards for standards: ISOSTS and NISO STS compared

In working with national standards bodies (NSBs), standards development organizations (SDOs), and other organizations that publish standards, we hear a lot of questions about the differences between ISOSTS and NISO STS. While ISOSTS and NISO STS are closely related—in fact, NISO STS was built on the foundation of ISOSTS—the differences are important, and will affect each organization’s decision on which of them to adopt.

But first…

Why standards publishers need XML

Using XML has many benefits for standards organizations of all kinds, including

  • Making multi-format, multi-channel publication easier
  • Improving internal and external linking
  • Improving content quality by simplifying integrity checks

A well-constructed XML publication workflow can also reduce time to publication and enable new products and features, such as a view that automatically shows differences between any two versions of a standard.

From ISOSTS to NISO STS

Both ISOSTS and NISO STS are based on JATS, the Journal Article Tag Suite (ANSI/NISO Z39.96-2015), and part of the “JATS family” with JATS and BITS (Book Interchange Tag Suite).

However, NISO STS is a formal standard (ANSI/NISO Z39.102-2017), whereas ISOSTS, originally designed just for NSBs, is not.

Because ISOSTS has been widely adopted in the NSB community, the NISO STS working group made sure that NISO STS is fully backwards compatible with ISOSTS. Thus, an organization that adopts NISO STS can still accept content marked up in ISOSTS without compatibility issues.

Some key improvements in NISO STS make it much more flexible than ISOSTS:

  • NISO STS has dramatically expanded metadata capabilities, designed to cover the needs of any standards organization, rather than being narrowly focused on NSBs.
  • ISOSTS has only the TBX model for Terms & Definitions. In contrast, NISO STS can accommodate both the TBX and Term Display models, allowing for a more display-focused modeling of the XML and reducing the burden of creating stylesheets to render in multiple environments.
  • NISO STS offers a new recursive model for adoptions.
  • NISO STS accommodates both XHTML and CALS tables, and both MathML2 and MathML3. In contrast, ISOSTS supports only XHTML and MathML2.

For a more comprehensive and technical look at the differences, see this NISO document.

The bottom line

If your organization is an NSB, you probably want to start with ISOSTS, but follow ISO’s lead about when to move to NISO STS. We expect ISO to upgrade to NISO STS in 2019 or 2020.


If your organization is not an NSB, you should adopt NISO STS from the start. This approach offers 100% backwards compatibility with ISOSTS documents (if needed) as well as additional functionality and improved metadata capabilities out of the gate.