Abstract: Software which uses text to speech technology to perform electronic screenplays, including plays depicting debates, multi-lingual conversations, and scientific conference presentations, using one or more distinctly identifiable voices. Screenplays are stored by the software as collections of text fragments whose relationships to each other have been documented in machine readable form, so as to make it possible for the software to comply with user requests that various aspects of the presentation be altered. This includes complying with user requests to increase or decrease the level of detail of a presentation, requests to increase or decrease the information density of a presentation, and requests to present again material that has already been presented using alternative wordings.