After the launch of the Mobile Web Initiative at the WorldWide Web Conference 2005, awareness is emerging that,today, mobile Web access suffers from interoperability andusability problems that make the Web difficult to use. Withthe move to small screen size, low bandwidth, and differentoperating modalities, technology is in effect simulating thesensory and cognitive impairments experienced by dis-abled users within the wider population of mobile deviceusers. The Third International Cross-Disciplinary Work-shop on Web Accessibility (W4A 2006) was targeted tobring together different communities working on similarproblems to share ideas, discuss overlaps, and make thefledging mobile Web community aware of accessibilitywork that may have been overlooked. The main questionasked was:‘‘Is engineering, designing, and building for theMobile Web just a rehash of the same old Webaccessibility problems?’’This lead to addressing issues such as:• Are the same solutions required for the Mobile Weband for accessibility and can the two communities worktogether to solve these problems?• What can the Mobile Web learn from the AccessibleWeb and what resources created to support theAccessible Web can be used by designers in theirsupport of the Mobile Web?• To cross-pollinate do we need to rethink the currentview of accessibility?Therefore, the workshop brought together a cross sectionof designers, engineers, and practitioners working on boththe Accessible and Mobile Webs; to report on develop-ments, discuss the issues, and suggest cross-pollinatedsolutions.The W4A 2006 was held on Monday the 22nd andTuesday the 23rd May 2006 as part of the FifteenthInternational World Wide Web Conference (WWW2006),running over 2 days, with 73 attendees and 20 papersaccepted for presentation. This special issue is an addi-tional outcome of the W4A 2006 Workshop, and consistsof the revised and extended version of seven papers of thepapers presented at the Workshop, selected on the basis ofthe review results. The articles presented here focus onmajor issues of the Accessible and Mobile Webs thatadvance the implementation of universal access.The first article in this special issue is entitled CapabilitySurvey of User Agents with the UAAG 1.0 Test Suite and ItsImpact on Web Accessibility by Watanabe, T. and Ume-gaki, M. This article discusses capabilities of a number ofJapanese user agents with respect to the User AgentAccessibility Guidelines (UAAG 1.0). This article high-lights that in order to promote Web accessibilityinternationally, the focus should not only be on contentaccessibility but also on user agent accessibility.It is a common belief that ‘‘A picture is worth a thou-sand words’’. That might be true for someone who issighted, but visually disabled users or users who work inenvironments where visual representations are inappropri-ate cannot access information contained in graphics, unlessalternative descriptions are included. The second article,which is entitled GraSSML: Accessible Smart SchematicDiagrams for All, by Fredj, Z.B. and Duce, D.A., investi-gates accessibility of diagrams. This article presents anapproach called Graphical Structure Semantic Markup