Do authors plan out series of books in advance?

Some series are actually one book divided into parts, like The Lord of the Rings. Or a book may prove so popular that the author is encouraged to continue writing about the same characters. Most often with popular fiction, the author chooses a storyline that requires multiple volumes, although she may write each book so it can stand on its own.

How does an author decide how many books to put in a series?

Each author and each series may develop differently. Bestselling author Jacqueline Diamond explains that when she wrote romances for Harlequin, it felt natural to plan them in three-book sequences, as with her Cops & Kids romances. However, she wrote each one so it could be read separately and feel complete to the reader.

The Doctor's Little Secret. Book One in the Cops & Kids series. When no-nonsense cop Rachel meets Dr. Handsome, she nearly claps him in handcuffs. Why on earth would she agree to a marriage of convenience? Kindle, Nook, Kobo, Smashwords, Googleplay or Apple.

Daddy Protector. Book Two in the Cops & Kids series. Detective Hale Crandall and his best friend's ex-wife are the best of enemies...until he has to run into a burning building to save a child. Can they reach a truce at last? Kindle. Nook.  Smashwords. Googleplay. Kobo. Apple.

Twin Surprise. Book Three in the Cops & Kids series. Her girlfriends bought him at a bachelor auction. Now she’s expecting twins! A heartwarming tale of second chances. Kindle, Nook, Kobo, Apple, Googleplay, Smashwords

The Police Chief's Lady. Book One in the Downhome Doctors series. Dr. Jenni Vine needs a fresh start, but are the town of Downhome and its handsome police chief prepared for a scandal? A Romantic Times top pick! Kindle, Nook, Kobo, Apple, Googleplay, Smashwords.