| Date | Publication | Publisher | Type | Page | |
|---|---|---|---|---|---|
| 1998 | Koontz III: Whispers / Watchers / Demon Seed | Berkley Books | Omnibus | ||
| 1999 | Watchers | Berkley Books | Novel | ||
| January 2003 |
|
Watchers (new Afterword) | Berkley Books | Novel | 3 |
| December 2003 | Watchers | Tandem Library | Novel | ||
| March 2004 |
|
Watchers | Brilliance Audio | Novel | |
| April 2004 |
|
Watchers | Brilliance Audio | Novel | |
| June 2004 |
|
Watchers | Brilliance Audio | Novel | |
| June 2004 |
|
Watchers | Brilliance Audio | Novel | |
| April 2006 |
|
Watchers | Headline | Novel | |
| May 2008 |
|
Watchers | Berkley Books | Novel | |
| May 2008 |
|
Watchers | Berkley Books | Novel | |
| June 2008 |
|
Watchers | Brilliance Audio | Novel | |
| December 2012 |
|
Watchers | Headline | Novel | |
| May 2018 |
|
Watchers | Brilliance Audio | Novel |