The Space Between (2013), a novella in the anthology The Mad Scientist's Guide to World Domination, later collected in A Trail of Fire (2012). It chronicles a journey undertaken by Joan MacKenzie (Jamie Fraser's step-daughter) and Michael Murray (Jenny Fraser Murray's son).
Virgins (2013), a novella in the anthology Dangerous Women. Set in 1740 France, it introduces 19-year-old Jamie Fraser as he and his 20-year-old friend Ian Murray become young mercenaries.
The Outlandish Companion (1999), a guide to the Outlander series containing synopses, a character guide, and other notes and information
The Outlandish Companion, Vol. II (forthcoming)
The Outlander series has been released in unabridged (read by Davina Porter) and abridged audiobooks (read by Geraldine James). Several of the Lord John books have been released in audiobook form, read by Jeff Woodman.
In 2010 Gabaldon adapted the first third of Outlander into a graphic novel, illustrated by Hoang Nguyen.
Outlander: The Musical
In 2010, a 14-song cycle based on Outlander was released under the title Outlander: The Musical. With music by Kevin Walsh and lyrics by Mike Gibb, the project was approved by Gabaldon after Gibb had approached the author in Scotland with the idea to adapt her novel into a stage production. As Gabaldon recalled, "I laughed and said, 'That’s the screwiest idea I’ve heard yet – go ahead.' So they did, and the results were stunning." Though the stage production remains in development, the 14-song cycle is available on CD from Amazon.com and for download on iTunes.
In 2012, Broadway composer Jill Santoriello began collaborating with Gibb and Walsh on the project, writing the music and cowriting the lyrics with Gibb for a new song called "One More Time." The song was recorded with vocals by Rebecca Robbins.
The Lord John series is a sequence of novels and shorter works that center on Lord John Grey, a recurring secondary character from the Outlander novels. The spin-off series currently consists of five novellas and three novels, which all take place between 1756 and 1761, during the events of Gabaldon's Voyager. They can be generally categorized as historical mysteries, and the three novels are shorter and focus on fewer plot threads than the main Outlander books. Several of the Lord John books have been released in audiobook form, read by Jeff Woodman.
^Martin, George R. R. (January 23, 2013). "Not A Blog: A Dangerous Delivery". GRRM.livejournal.com. Retrieved January 23, 2013. "For those who like to lose themselves in long stories, the Brandon Sanderson story, the Diana Gabaldon story, the Caroline Spector story, and my Princess and Queen are novellas."