Guest blogger Mindy Klasky is the author of six fantasy novels, including the award-winning, best-selling The Glasswrights’ Apprentice and numerous short stories. Her latest novel, Sorcery and the Single Girl, is the second book in a series about a love-struck D.C. librarian who discovers she’s a witch. A portion of proceeds from the sale of Sorcery and the Single Girl, available starting September 25th, and Girl’s Guide to Witchcraft, available now, will benefit First Book.

What makes a book become a bestseller? Obviously, the book sells “a lot” but what exactly does that mean? Everyone in the book industry claims to have an answer.

The New York Times bestseller list - the one that most authors would give their keyboards to make - considers several elements, including:

• How many copies of the book sold to certain booksellers (not individual buyers)?
• How rapidly were those sales made? Were re-orders placed for the book very quickly?
• What was the format of the book? Was it trade paperback (oversized, often literary, paperbacks), which is given more “credit” than mass market paperback (the standard “pocket” paperbacks), given the higher cost of trade?

Many factors go into our scientific analysis. We wonder if enough copies of our books were printed in the first place, to even give us a chance of making the list. We wonder if those copies shipped promptly. We wonder if they were shelved by bookstores promptly. We wonder if the covers were faced out (luring readers more than spine placement). We wonder if sales are reported accurately. We wonder if we’re crazy for spending so much time wondering.

Most of bestseller-dom is completely beyond an author’s control. We can tell family, friends, and fans about upcoming releases. We can explain the process, as best we understand it. And then we have to sit back and ride the roller coaster of our book’s release.

For the record? SORCERY AND THE SINGLE GIRL, the second book about Jane Madison, a librarian who finds out that she’s a witch, debuts on September 25. The publisher has printed enough copies that it *could* make the bestseller list, if enough copies are bought quickly enough. Ten percent of all profits go to First Book. Want to help with a science experiment? Buy a copy of SORCERY next week!

And in the meantime, let me know in comments to this post what you think makes a bestseller! What do you look for in a great read? What common elements do you find in most of the bestseller books that you see in stores?