Although most writers and self-publishers know what ISBN is and what the acronym stands for, I continually run across those who don’t really understand its importance to their books and their publishing ventures.

First, I thought I would just point people to the appropriate section in one of the many excellent self-publishing reference books. So, I grabbed three of them off my reference shelf and began looking.

Odd. They all talked about ISBN, what it is (in very basic terms), how to get it, and what to do with it. But not one clearly described why it’s important and why decisions regarding how to acquire and use ISBNs are so important.

So, lets try to make some sense out of the confusion and misunderstanding surrounding ISBNs, primarily from a US-centric view (that’s what I know most about). I hope this helps those of you who have yet to make your decision on this critical item.

ISBN = International Standard Book Number

You knew that already, right?

The ISBN can be found in numerous places:

• Back cover of a book (with the bar code)
• Book’s copyright page (the back side, or verso, of the title page)
• Book catalogs
• Book’s detail page at online retailers (like Amazon.com)
• Book’s internal metadata for eBooks
• Industry databases (like R. R. Bowker’s Books-in-Print).

In the US, you can buy your ISBN(s) directly from R. R. Bowker, the designated US ISBN agency, at MyIndentifiers.com. You can buy a block of 10 for $250 or a block of 100 for $575 (you can buy larger blocks, if you wish). All ISBNs in an assigned block identify the publisher through the “publisher prefix.”

You can also buy a single ISBN from Bowker for $125, making this a very expensive option. And you will not own a “publisher prefix” that will be included in subsequent ISBNs for your subsequent books. You will only own that single ISBN.

The ISBN is an industry-wide standard to identify a specific title, edition, and format for a particular book. If you issue a single title as a paperback, hardcover, and e-book, you will need three separate ISBNs. If you significantly revise your title (as a second edition, for example), you will need to assign it a separate ISBN. If you write three or four books, you can quickly use up a block of 10 ISBNs.

Many subsidy publishers (usually, these days, calling themselves “POD publishers” or “self-publishing companies”) will offer to provide you an ISBN for your book. Be aware that any ISBN provided by them for your book will identify that subsidy publisher as the publisher-of-record for the book.

Not you. Which means you are not really the publisher, regardless of what that publisher tries to tell you or might imply.

Why should you care?

Suppose you publish your book through Amazon’s CreateSpace and allow them to assign it an ISBN. Two years later, you decide you prefer to print your book with another printer or even a different subsidy publisher. Your book MUST be assigned a new ISBN, since the original one was owned by the original publisher (CreateSpace in this case). And that original ISBN can never be reassigned to a different book, even if the publisher declares their edition of your book as out-of-print.

From that point forward, your book will have two ISBNs associate with it. If a bookstore or library tries to order it, they will have to guess which one is the current one. You will have to rely on some (possibly clueless) clerk to make that guess. They may just pick the first one they stumble on. If that one turns up as OP (out-of-print) or otherwise unavailable, that’s what they’ll tell the customer.

And those two version of your book will continue to show up on Amazon with different publishers, possibly different prices, etc. An Amazon search on your title may not turn up the current version near the top of the results (or, possibly, at all).

You want to avoid this kind of confusion in the marketplace at all costs, if you expect to build your sales for the long haul.

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