A series of sci-fi / comedy novels by Douglas Adams.

A series of books based on the Harry Potter series by J K Rowling.

A spin-off from the Bill Hodges series by Stephen King featuring Holly Gobney introduced in Mr Mercedes.

A series of science fiction books written by Orson Scott Card in the 90s.

A series of science fiction books written by Brian Stableford.

A series of novels based on a character created by Clarence E Mulford in 1904.  This series are the novels written by Loius L'Amour.

A science fiction series by Alastair Reynolds.  As of this time is consists of two short-stories and a novel.

A series of fantasy novels by Diana Wynne Jones.

A series of distopian science fiction by Suzanne Collins geared mostly to the teen and young adult audience.

A series by M A Carey.

A series of science fiction novels by Dan Simmons.

A science fiction subseries set in the Humanx Commonwealth Universe by Alan Dean Foster.

A series within the Tortall universe.  These four collected in the one volume titled The Immortals.

The second trilogy of Kushiel's Legacy.

A fantasy series written by Christopher Paolini.

Inheritance Trilogy by N K Jemisin.

The first published trilogy of books in the Revelation Space series by Alastair Reynolds.

A series of fantasy books written by Cornelia Funke.

A series of stories written by Josephine Tey.

A science fiction dualogy by Larry Niven that takes place in the State / Leshy Circuit series of books.  The series is also known by some as Smoke Ring.

A series of science fiction novels by John Scalzi.

A science fiction series by Lloyd Biggle, Jr

A series of science fiction from John Brunner.

A series of fantasy novels by Carole Nelson Douglas.

A fantasy series written by John Morressy

A series of fiction novels written by Michael Connelly featuring crime reporter Jack McEvoy.  These take place in the world of Harry Bosch.

A series of action / adventure novels by Lee Child and later also by Andrew Child featuring the main character Jack Reacher.

A series of novels written featuring the character Jack Ryan created by Tom Clancy or taking place in the same fictional world.  I've only included books written by other authors and not by Tom Clancy in this list.

A series of novels written by Tom Clancy featuring the character Jack Ryan or taking place in the same fictional world.  I've only included books written by Tom Clancy in this list (even if he collaborated).

A sci-fi series by Ron Goulart.  This is a sub-seris of the Barnum System.

A science fiction trilogy by William Gibson.

A science fiction series by Keith Laumer with Jame Retief as the main character.

A series of fantasy novels by Sharon Green

A science fiction series by Rivers Coffman.

A series a spy thrillers written by Ian Fleming in the mid-20th Century that went on to become a somewhat successful movie franchise.

An action/adventure series written by Dean Koontz featuring Jane Hawk, a former FBI agent on the run.

A series of books written by Robert Ludlum.  Other authors have also contributed - but they are not included in this series.

The fifth the Dray Prescot series.

A science fiction series by Dan Simmons

A fiction series written by C J Box.

A action-adventure fiction series by Tom Clancy which is a part of the Jack Ryan world.

A series of stories written by Rudyard Kipling.

Series of books by Michael Crichton.

A fantasy series by John Morressey

A series of fantasy novels by Piers Anthony and Robert E Margroff.