Jeanne Spellman, W3C Web Accessibility Initiative
The World Wide Web Consortium (W3C) is an international community that develops open standards, protocols and guidelines that ensure the long-term growth of the Web.
One of its working groups is the Authoring Tool Accessibility Guidelines Working Group (AUWG)
How WAI Develops Accessibility Guidelines through the W3C Process
ATAG 2.0 Part A Applicability Notes
Implementing ATAG 2.0 B.1
Implementing ATAG 2.0 B.4
From the ATAG Test Harness Home page: