The Value of Involving People with Disabilities in User Research (Sarah Horton)

I am a huge fan of the Web Content Accessibility Guidelines (WCAG) as a means to measure progress toward accessibility. They are thorough and well considered. They are flexible. I have used them to evaluate desktop applications, mobile apps, mobile sites, websites, and web applications. They go far in removing subjectivity from the assessment process—a control either is or is not operable using the keyboard; a text input either has or does not have a programmatically associated label. (usertesting.com)