In 2009, the number of self-published books released in the US exceeded the number of new titles from conventional publishers for the first time in history. Now, a similar pattern is emerging overseas. Until recently, costly transatlantic shipping, different trim sizes and business models, and language barriers conspired to segregate the US author-publisher from foreign markets, and vice versa. But the tide has started to turn, driven by Print-on-Demand (POD) technologies. A spokesperson for POD printing giant Lightning Source says, "Ingram Content Group has over 100 author services publishers who print in the UK using Lightning Source… On average, we're seeing over a million units printed annually as well as double digit growth."

With POD, books can be printed on either side of the Atlantic without prohibitive shipping costs; trim sizes can be adjusted painlessly, say from 6x9" to Royal format, or from 8.5x11" to A4. Driven almost universally by POD, self-publishing companies such as Author Solutions, Blurb, Café Press, CreateSpace, Lulu and Wordclay now offer US writers greater access than ever to overseas markets. And the road runs both ways: foreign writers can use POD companies to gain a toehold among American audiences, usually in niche markets outside bookstores and libraries.

According to Kevin Weiss, CEO of Author Solutions, "AuthorHouse UK in 2005 was our first international venture and it has experienced steady growth every year. AuthorHouse UK's success has been [a] catalyst for expansion of our Xlibris imprint, as well as our partnership imprint Balboa Press, into European markets."

Like many companies that sell book publishing services to aspiring writers, Author Solutions has much of its printing done by Lightning, which has production facilities in the US and UK, and will open a plant in Australia this summer. "The expansion of our Lightning Source global print solution into Australia provides publishers with expanded market reach and sales opportunities that were impossible in many cases," says Skip Prichard, President and CEO of Ingram Content Group.

Lulu.com is another major force in the self-publishing world, and its founder, Bob Young, sees international expansion as a key to growth. "Yes, our global ambitions continue," Young says. Born in Canada, Young made his fortune taking Red Hat Linux public in 1999, and self-published his memoir – Under the Radar – about it, leading to his founding of Lulu in 2002.

Perhaps the most globally-oriented of the leading DIY self-publishing services, Lulu, has sites in six languages, allowing writers to self-publish books in a variety of international trim sizes, with e-commerce in half a dozen currencies. More than a million writers from 200 countries have published at Lulu to date.

A book ordered from Lulu is printed at the most appropriate geographical location, from the US to the UK to France. Like Author Solutions, Lulu sends many print orders to Lightning. Lulu also has printing arrangements with Central Bookhouse (Centraal Boekhuis) in The Netherlands.

At this stage, American authors are only starting to take advantage of POD production options in the Benelux countries, where English is widely spoken. Mathijs Suidman, Manager of Digital Services for Central Bookhouse, explains: "My take is that currently local DIY publishers in [the] EU are more successful due to the local approach… local ISBNs, local marketing etc."

Looking to future of self-publishing in the UK and EU, some industry observers predict a steep upward trajectory similar to the one seen in the US between 2005 and 2010. "In the US, self-publishing is [now] the rule, not the exception; but internationally the growth potential for this model is virtually untapped," says Author Solution's Kevin Weiss.

A 2005 study by the Book Industry Study Group found that book sales outside bookstores and libraries in the US now total at least $11 billion annually. A substantial portion of these "non-traditional" sales is attributable to self-published books. In 2011, the self-publishing boom is spreading from the US to the UK, with further growth imminent in the EU and Australia.

Danny O Snow founded Unlimited Publishing LLC in 2000. He previously served as Director of Communications and Planning for 1stBooks (now Author Solutions) and later as Senior Planning Consultant for Lulu Enterprises.