The World Wide Web (W3C) Web Accessibility Initiative has developed comprehensive guidance on evaluating web accessibility. Web Content Accessibility Guidelines (WCAG) 2.0 specifies the success criteria for evaluating the conformance of web pages. In this paper, we explore the potential of applying the structured assurance case methodology, which has been used with success in assuring safety cases, to measure adherence of a web page to WCAG 2.0 conformance requirements. The paper summarizes the results and provides a detailed description of the work. Finally, the paper summarizes some lessons learned from the approach.