In a concession to market realities, National Geographic is publishing its largest book of photographs ever—504 pages of pictures spanning a century— at a relatively modest $30. "The market is very soft and we wanted to be able to offer a great value to people who would be interested in tasting National Geographic," said Nina Hoffman, president of National Geographic's Books and Education Publishing Group.

The October release, Through the Lens: National Geographic Greatest Photographs, includes images that are decades old. But the publisher's cost-conscious approach is very up-to-the-minute. Hoffman says the old rules about pricing don't apply anymore. "I think there's a ceiling now in the world of illustrated books," Hoffman said. "I think the ceiling is really $40. I think anything above $35 really causes the customer to pause."

There was a time when the publisher didn't hesitate to scrape that $40 ceiling—or even break right through it. In 1994, the retrospective title National Geographic: The Photographs sold for $50 and was 336 pages. In the decade between those two titles, the publisher has routinely priced books of between 300 and 400 pages at $40 or $50.

What made the lower price possible, noted Hoffman, was the cooperation of partners in 20 countries publishing the book simultaneously. "What it really speaks to is the power of coproductions. When we join together we can get an economy of scale and it's an economy of scale we wanted to give to the customer," she said.

The strategy seems to be working. About 400,000 copies have been printed worldwide so far, 160,000 in the U.S. With publicity hits from appearances on CNN, CBS Sunday Morning and The Today Show, the book has ranked as high as number four on Amazon.com. It also hit the top spot on Barnesandnoble.com, where it sold at the discounted price of $21.