(written from a Production point of view)
Diane Elizabeth Duane (born 18 May 1952; age 64) is the author of numerous Star Trek novels, including The Wounded Sky, Doctor's Orders and Spock's World (Pocket TOS), Dark Mirror and Intellivore (Pocket TNG), and the Rihannsu series – My Enemy, My Ally, The Romulan Way, Swordhunt, Honor Blade, and The Empty Chair. She also created a Romulan language for the Rihannsu novels.
Diane Duane has worked with Star Trek in perhaps the most forms of anyone alive. Besides comics, novels and TV, she has adapted her own work for audio, has written for the Star Trek manga series by Tokyopop, has written short Trek fiction for anthologies, and plotted and wrote the first Star Trek computer game, Star Trek: The Kobayashi Alternative.
Duane has also written more than thirty non-Trek books; among these she is probably best known for the Young Wizards series,  which is currently in its eighth volume. Other books include the "Feline Wizardry Sequence" and the Door... series. She makes a habit of including Star Trek references in her non-Trek books.
A character in "Debt of Honor", a comic from DC, was named for Diane Duane – a Diane Morwood was the third-in-command of the engineering section of the USS Farragut, and a colleague of Lieutenant James T. Kirk, in 2254.