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[ROUGH CONCEPT DRAFT] Transitioning Web Sites from WCAG 1.0 to WCAG 2.0

Note: This document is a rough draft in development, and should not be referenced or quoted under any circumstances.
$Date: Wednesday 17 January 2007 - 20:18:30changelog]

Page Contents

This guide highlights key steps for designers, developers, and project managers when transitioning a site from Web Content Accessibility Guidelines 1.0 (WCAG 1.0) to Web Content Accessibility Guidelines 2.0 (WCAG 2.0). Each step is introduced with a supporting resource document.

WCAG 2.0 builds on WCAG 1.0 and is designed to apply to more advanced Web technologies, be easier to use and understand, and be more precisely testable. Sites built to WCAG 1.0 will already be a long way to fulfilling WCAG 2.0 as it is backwards compatible with WCAG 1.0. As such, existing accessibility work is still valid and in many cases work needed to transition to WCAG 2.0 may be minimal.

For more information on the benefits of WCAG 2.0 please refer to "The benefits of transitioning to WCAG 2.0" (future link).

1. Learn the Basic Differences

Resource: Overview of WCAG 2.0 Documents lists the WCAG 2.0 documents and introduces Differences in approach between WCAG 1.0 and 2.0.

Having read the Overview the key differences you need to know are differences in approach and terminology (such as checkpoints changing to Success Criteria) , and how the new concept of Baseline underpins your Conformance claim.

2. Clarify Your Baseline and Conformance Goals

Note: What we refer to as requirements in this page are the WCAG 1.0 Checkpoints and is the WCAG 2.0 Success Criteria.

To establish what requirements you will need to meet under WCAG 2.0 first decide your Baseline and Conformance levels. If your organisation already has an Accessibility Policy that is updated to WCAG 2.0, Baseline and Conformance should be outlined here.

If you want information to help you develop an Accessibility Policy the document Developing Organizational Policies on Web Accessibility outlines key considerations. "Transitioning Web Accessibility Policies from WCAG 1.0 to WCAG 2.0" is a future document which will provide guidance on transitioning Accessibility Policies.


Note: this section will be revised after the concept of Baseline has been stabilised.

Resource: About Baseline in WCAG 2.0 provides information about what the baseline concept is, key considerations when deciding a baseline and example baselines.

Once the Baseline is established there are a number of key things to understand

  1. What technologies are relied upon and not relied upon within your site.
  2. How Baseline impacts your Conformance claim.
  3. Dependant on Baseline and Conformance, what techniques will need to be implemented.


Note this will be revised after About Baselines in WCAG 2.0 is updated.

Resource: Conformance WCAG 2.0 provides information about levels of conformance, how to scope a site and how to write a conformance claim.

You will need to understand:

  1. How the WCAG 2.0 Conformance scheme works and differs from WCAG 1.0.
  2. How to scope a Web site using the WCAG 2.0 Conformance scheme.
  3. What things might impact what you choose for conformance such as internal policies and legal policies that exist for your country, region or organisation type.

Note that you might refine your conformance goals after you have completed a more in-depth analysis of the technical differences, as described below in section 3.

3. Analyze How the Technical Requirements Apply to Your Site


Two key areas to review are:

3.1. Check what WCAG 1.0 Checkpoints map to WCAG 2.0 Success Criteria

Key questions to ask your self are:

3.2. Check new WCAG 2.0 Success Criteria

Review the quick reference document, Comparison of WCAG 1.0 checkpoints to WCAG 2.0 "New ones", for a list of new Success Criteria. Key questions to ask are:

4. Plan and implement Changes to Your Site


Once you have reviewed the differences between WCAG 1.0 and 2.0, you can then plan changes to your site(s). To do this:

5. Update internal guidance

Resource: Techniques for WCAG 2.0 provides techniques for meeting the WCAG 2.0 Success Criteria. This document will be updated over time as new techniques and Web technologies evolve.

Based on the changes made when updating your site(s) to WCAG 2.0, review and update any internal Web content development guidance and processes. You will need to refer back to the "Techniques for WCAG 2.0" document on an on going basis because while the Guidelines and Success Criteria of WCAG 2.0 will not change, the techniques may develop together with technologies as well as assistive technologies. This will enable you to evolve your Web site as new technologies evolve and still meet Success Criteria.

The ongoing maintenance is a positive thing, there will be more tips and checks and as technology evolves so will the support and guidance available. It has been written to allow your site to evolve as technologies evolve. As such WCAG 2.0 is flexible, scalable and adaptable.

When the WCAG 2.0 Techniques are updated, WAI will announce this on the home page and via the IG mailing list. To get WAI announcements, you can subscribe to the following: