(Art design courtesy of Janet Hansen. Photo courtesy of Riverhead Books) (Art design courtesy of Janet Hansen. Photo courtesy of Riverhead Books)

No matter how rusty you are at the Dewey Decimal System, you can quickly get your bearings in a Little Free Library. These very small buildings — or very large bird houses — offer books on a take-one-leave-one basis. Since this quixotic idea took hold in Wisconsin in 2009, around 15,000 diminutive collections have started operating all around the world — in the open, unsupervised, without shhhhing.

Now, Riverhead Books is joining this tiny building craze. To celebrate its 20th anniversary, the publishing house is donating three Little Free Libraries to communities around the country. This week, the first one was shipped off to Rochester, N.Y., a community selected by David Schickler (“The Dark Path,” Riverhead, 2013). Another Riverhead author is helping the publisher select an interested community out West for the second library.

But placing Riverhead’s third Little Free Library comes with a dash of suspense and competition. The publisher has launched a contest to determine the winning site. Junot Díaz, Emma Straub and Dan Pink will select five finalists from community applications and then let the public vote on where it should go.

“We are constantly looking for new ways for readers to discover our books – digitally and physically,” says Riverhead publisher Geoff Kloske. “When I learned that these were popping up around the country, it made perfect sense that we would go into the library construction business.”

LittleFreeLibrary.org, the national organization’s Web site, offers plans and construction advice, but these three Little Free Libraries were designed by the Riverhead art department, headed by Helen Yentus. She conducted her own contest among her staff, and then the publisher chose the winning designs.

“I love a design challenge,” Yentus says. “Earlier in the year, I was asked to create a 3-D slip case for Chang-rae Lee’s ‘On Such a Full Sea,’ so this wasn’t such an unusual request. The talented artists and craftsmen Dan Bina and Aaron Black of Kahokia Design in Brooklyn fabricated and painted them. The libraries are very solid and well-constructed and meant to survive outdoors. Cost is, of course, always a concern, but this is for charity and in celebration of our anniversary, so the expense was well worth it.”

These libraries may be diminutive, but Riverhead is thinking big. Each Little Free Library it donates comes filled with some of the publisher’s most popular books, such as Khaled Hosseini’s “The Kite Runner,” James McBride’s “The Color of Water,” Meg Wolitzer’s “The Interestings,” Emma Straub’s “The Vacationers,” Anne Lamott’s “Help Thanks Wow” and more.

“We’re still figuring out how many we can pack in there,” Yentus says.

Words every librarian can relate to.