Spacer Dreams (1995)
The Four Magics (1996) (with William R Forstchen)
Alien Dreams (1997)
Wizardspawn (2003)
Nightmare Logic (2004)

Great Cat Mysteries (1996) (with Joan Hess, Sharyn McCrumb)

Net Force (with Tom Clancy, Steve Perry)
8. Changing of the Guard (2003)
9. Springboard (2005)
10. The Archimedes Effect (2006)

Cat Crimes (with Ed Gorman, Martin H Greenberg)
Cat Crimes for the Holidays (1995)
Cat Crimes Through Time (1998)

Fantastic (with Martin H Greenberg)
Spell Fantastic (2000)

Murder Most... (with Ed Gorman, Martin H Greenberg)
Murder Most Feline: Cunning Tales of Cats and Crime (2001)

First Contact (1987) (with Martin H Greenberg)
Future Net (1996) (with Martin H Greenberg)
An Anthology of Angels (1996) (with Martin H Greenberg)
Battle Magic (1998) (with Martin H Greenberg)
Far Frontiers (2000) (with Martin H Greenberg)
Guardsmen of Tomorrow (2000) (with Martin H Greenberg)
Past Imperfect (2001) (with Martin H Greenberg)
Silicon Dreams (2001) (with Martin H Greenberg)
Future Wars (2002) (with Martin H Greenberg)