The publication of EPUB3 has been a major step forward digital publishing. Relying on Web Technologies like HTML, CSS, SVG, and others, EPUB3 offers a solid basis to publish not only digital books, but all sorts of digital publications in a portable, adaptable and accessible manner. However, it is possible to bring the publishing and the Web world even closer together, making the current format- and workflow-level separation between offline/portable and online (Web) document publishing eventually disappear. These should be merely two dynamic manifestations of the same publication: content authored with online use as the primary mode can easily be saved by the user for offline reading in portable document form. Content authored primarily for use as a portable document can be put online, without any need for refactoring the content. Essential features flow seamlessly between online and offline modes; examples include cross-references, user annotations, access to online databases, as well as licensing and rights management. W3C and IDPF have recently started to work towards this vision, exploring the technical challenges to make it a reality; this talk will give an overview on where we are.