Storyline 3 lets you create courses that support Web Content Accessibility Guidelines (WCAG).
Storyline 3 HTML5 and Flash courses support WCAG, including screen reader support, full keyboard navigation, visible focus indicators, and more. See this article for design recommendations.
Accessibility How-To Articles
See these articles to learn more about authoring accessible courses:
Screen Reader Support
Storyline 3 supports these screen readers with HTML5 and Flash courses: