If you've written a book and are about to self-publish it, you're likely looking into many things, including how to get an ISBN. Virtually every publishing industry pro advises authors to have ISBNs for their books. It connects you to the global book supply chain in a way that's valuable time and again. Each country has its ISBN registration agency, and in the United States, it's Bowker. There is a cost for U.S. authors, but discounts exist for multiple numbers to bring down their price considerably. In other countries, ISBNs are free. But whatever the cost, they are worth it, and every book needs to have one.

Once you have an ISBN, it's crucial to enter your book's title, author, subject category, price, and description. Together, it is referred to as the metadata. Once complete, it is sent to booksellers, libraries, and search engines so that your book is indexed along with millions of others. Because books often have similar titles, the ISBN makes sure your book is uniquely and correctly listed. Accurate metadata is required for effective book marketing, and you need to keep it up-to-date if there are any changes, such as a higher or lower price. For self-published books, list yourself as the publisher.

You can purchase or apply for, depending on your country, an ISBN at any stage of the publishing process. ISBN should not be confused with copyrights that occur automatically as your work is written. Also, there is no such thing as an e-ISBN. The same numbering system is used for print and digital products. Therefore, whatever the product, you have an ISBN. As an independently published author, establishing credibility is crucial. Having an ISBN and working within the industry system is highly advisable. While some books do not have one, they rarely succeed commercially.

Because the world is increasingly data-driven today, systems like ISBNs have taken on greater importance. They provide clarity and let people in various parts of the book publishing world know about your work – and list it distinctly. Search engines also are crucial to people finding out about your book (its discoverability), and because they value ISBNs, you want to have one as well. While something is appealing to some about being a maverick and going it on your own, this is a case where it will be a handicap in the long run. Make sure you give your book every chance of becoming a success.