This paper presents requirements for a cybertext authoring system in the literary domain. Issues discussed include a drawing framework; pluggable objects; openness to a variety of different types of structure, including piles, relations, sets, links, and composites; flexible behavior (extensibility and tailorability); dependency control; non-binary file formats for export and import; web-enabled player; and portability. Issues relevant to structural computing appear throughout, as structural computing is the only paradigm likely to support all of these requirements.