(written from a Production point of view)
In the late 1990s, Simpson worked as a freelance editor for Simon & Schuster, alongside friends Marco Palmieri and Margaret Clark. During his time there, Simpson and Palmieri began to work on pitches for Star Trek: Deep Space Nine, including one where Jennifer Sisko survived the destruction of the USS Saratoga by being assimilated by the Borg. Although the series' final storylines had already been determined by the time the two came to pitch, Palmieri would use the elements of that pitch in developing the Deep Space Nine relaunch series, and asked Simpson to write the novel in which that story occurred. (Voyages of Imagination, pp. 264-265)
Simpson also worked on the The Lives of Dax anthology, developing and plotting the Joran Dax short story "Allegro Ouroboros in D Minor". However, after Simpson struggled to make progress with drafting, Palmieri suggested he provide what he had written to date to S.D. Perry, who completed the manuscript and shared credit with Simpson on the final story. (Voyages of Imagination, p. 611)
Simpson also wrote the novel Sid Meier's Alpha Centauri: Centauri Dawn.