In this article, we describe what we expect will be a substantive transformation in health sciences education: Health Sciences Online (www.hso.info). HSO is the first website that delivers authoritative, comprehensive, free, and ad-free health sciences knowledge. It is a portal to the best health sciences knowledge, and the foundation of what we expect to be the most accessible, high-quality health sciences university. This article describes the site and the resources currently available through HSO, and our plans for further development of this resource.