- *Fire Seed* (2000)
- *Dark Horse* (2002)
- *The Veil of Green* (2004)
- *The Last Song of Reign* (2007)
- *The Rightful Heir* (2011)
Nonfiction
- *The Art of the Enneagram* (2005)
- *Enneagram for Dummies* (2015, with Elizabeth Wagele)
- *Enneagram at Work* (2019, with Elizabeth Wagele)