[I originally wrote this a couple of years ago, and decided that I should now share it more widely. I have edited the original to better reflect a wider audience.]
The attached timeline is intended to serve more as a rough guideline rather than a specific series of milestones. It is the responsibility of any Project Owner to ensure that accessibility reviews are undertaken throughout the life of any project: the overall goal is to avoid 11th hour accessibility reviews that are doomed to failure due to lack of earlier planning.
Phase 1: Plan for Accessibility
At the earliest stage of any project, the Project Owner should ensure that accessibility requirements are being integrated into the project. This might involve an internal review of in-house participants, or requesting an external Subject Matter Expert (SME) be contacted. Many large organizations already have a designated Accessibility specialist or Accommodation officer: if that person is unable to directly assist you they likely can help you find an appropriate candidate. It is the responsibility of a Project Owner to ensure that accessibility goals are part of the larger project.
Phase 2: Involve Accessibility Subject Matter Experts at the Specification Level
As the development of Functional Specifications near finalization, it is important to ensure that accessibility goals are being sufficiently addressed. As Functional Specifications move towards early Technical Specifications, involving your previously identified SME or consultant will assist in ensuring that the project is on track and that no Functional or Technical proposal introduces unforeseen access barriers or issues.
The W3C WCAG 2 guideline is structured in such a way as to focus on overarching issues that may impose barriers, yet is specifically designed to allow flexibility in developing successful solutions. While this flexibility leaves open room for evolving solutions, it also implies a certain level of subjective interpretation – an area where subject matter expertise is a valuable asset. Because of this, a close review of the guidelines at this time will provide the largest payoff in terms of ensuring a successful resolution.
Phase Three: Get Sign-off that Your Project has met Accessibility Goals
As the project nears the mid to late development phase, the developers should be verifying that solutions created have met the accessibility requirements. This ensures that as the project moves to the Testing and Q/A phase, accessibility requirements have been met.
The final testing and Q/A phase should specifically allocate time and resources to ensure that accessibility requirements have been addressed.