"Pioneer Girl," Laura Ingalls Wilder's autobiography — annotated and illustrated and published in lovely large-book format, with a full-color dust jacket — was the book that caught everyone by surprise last winter.

The book had been in the works for three years and its publisher, South Dakota Historical Society Press, had planned a print run of 5,000 — that's a lot for a regional, academic press.

"Our usual print run is about a thousand," said the press director, Nancy Tystad Koupal. But when they got ready to place the printing order last October, they already had online orders for 7,000. So they bumped the print run up to 15,000.

"It was a little bit of a risk," Koupal said. "It wasn't a cheap decision."

She needn't have worried. Those 15,000 copies were gone in a flash. The books arrived at the warehouse on Nov. 14 and by Dec. 12 they were gone.

The press ordered a second printing of 15,000. "We agonized over that, too," Koupal said. "We probably had another 8,000 orders at that point. So we took a chance and ordered another 15."

But long before that second print run showed up at the warehouse, the big boys started calling. Amazon had a huge order, she said. So did Barnes & Noble. It was too late for the holidays; many who had ordered the book for Christmas were forced to wrap up I.O.U.s as gifts, or hastily buy a substitute present.

"At the end of December, we were finally getting the kinds of numbers that we could have used much earlier to greater advantage," Koupal said. The press wasn't used to dealing with big online retailers; that's not the kind of book they normally publish.

In January, the press ordered a third printing — this time, 45,000 copies. "That one was scary," Koupal said.

One of her worries was cash flow — printers give publishers 60 days to pay the bills, but bookstores and distributors have more than twice that time to pay the publisher.

"Managing all that, for a small press — it was some scary days and nights," Koupal said. "It all worked out, and I'm happy."

It was not, however, fun.

"People were saying, 'Where's my book?' And there was nothing we could do about it," she said.

So far, the book has gone into seven printings. There are now 150,000 copies in print and it is, once again, readily available.

"We have ordered an eighth printing to be sure we get through the holidays in a much happier fashion," Koupal said. "We just don't know what the fall will bring, but we want to be well and truly prepared. Plus, the book hasn't even been out a year. We don't want to be caught short again.

"This has been a bit of a roller coaster. Our usual goal is to break even, and we're hoping this one will give us a little spending money for the future.

"Here's this book, it's got over 800 notes, it's got all these scholarly apparatuses, and while we tried to make it really attractive — I love books, I love beautiful books — I never thought in a million years that it would hit the New York Times bestseller list," she said.

Which it did, for six weeks.

"But isn't it great?"