"Savage Empire" series

• Savage Empire (1981)
• Dragon Lord of the Savage Empire (1982)
• Captives of the Savage Empire (1984)
• Flight to the Savage Empire (1986) (with Winston Howlett)
• Sorcerers of the Frozen Isles (1986)
• Wulfston's Odyssey (1986) (with Winston Howlett)
• Empress Unborn (1988)
• Dark Moon Rising (omnibus) (2004) - reprinted collection of the first three novels
• Prophecies (omnibus) (2004) - reprinted collection of the fourth and fifth novels

"Nessie" series (with Lois Wickstrom)

• Nessie and The Living Stone (2001)
• Nessie and the Viking Gold (2003)

"Sime/Gen" series

• First Channel (1980) (with Jacqueline Lichtenberg)
• Channel's Destiny (1982) (with Jacqueline Lichtenberg)
• Ambrov Keon (1985)
• Zelerod's Doom (1986) (with Jacqueline Lichtenberg)
• The Unity Trilogy (2003) (omnibus) (with Jacqueline Lichtenberg)

Non-series novels

• Pandora No 6 (1980)
• Blood Will Tell (2001)

Star Trek series contributions

Star Trek

• Full Moon Rising (1976)
• The Night of the Twin Moons (1976)
• Epilogue: Part I (1977)
• Epilogue: Part II (1978)

Star Trek : The Original Series

• The Vulcan Academy Murders (1984)
• The IDIC Epidemic (1988)

Star Trek : The Next Generation

• Survivors (1988)
• Metamorphosis (1990)