The VoxBoox system makes digital books accessible to visually impaired individuals via audio and voice. It automatically translates a book published in HTML to VoiceXML, and then further enhances this VoiceXML rendering of the book to enable listener-controlled dynamic aural navigation. The VoxBoox system has the following salient features: (i) it leverages existing infrastructure since the book that is to be made accessible need only be published digitally using HTML on the visual Web, (ii) it is based on accepted Web standards of HTML and VoiceXML and thus books can be made accessible inexpensively, and (iii) it is user-centered in that the listener (the user) has complete control over (aural) navigation of the book. In this paper, we present details of the technologies that make the VoxBoox system possible, as well as the details of the system itself. A prototype of the VoxBoox system is operational. Categories/Subject Descriptors: H.5.2 [User Interfaces]; General Terms: Human Fact...