What author wrote the Baby-Sitter's Club book series ?

The Baby-Sitters Club (also known as BSC) is a series of novels written by Ann M. Martin and published by Scholastic between 1986 and 2000, that sold 176 million copies.

The series is about a group of middle school students living in the fictional town of Stoneybrook, Connecticut. They run a business called "The Baby-Sitters Club" that helps parents find babysitters from the club who are available for jobs by calling during their club meetings. The club starts out with four members: Kristy Thomas, Mary Anne Spier, Claudia Kishi, and Stacey McGill; it eventually expands to ten. When the club was founded, the four members were in the seventh grade, but ten novels later, they are promoted to the eighth grade. From there, they are frozen in time until the very end of the series, in which they graduate from middle school. A notable facet of the series is that each novel contains at least one subplot dealing with different issues the girls face.

As of December 31, 2009, The Baby-Sitters Club series was out of print. However, in April 2010 the series was re-released with updated versions of certain volumes of the original series, as well as a newly written prequel.