Two decades ago, when Assouline, a leading purveyor of high-end coffee table books and fancy library accouterments, opened its first branded outpost on the seventh floor of Bergdorf Goodman in New York, Prosper Assouline, a founder of the company, experienced a kind of epiphany.

“I noticed that luxury consumers were willing to spend $650 on shoes,” he said in a recent interview conducted by video from his home in Paris. A compact man with a penchant for fastidious tailoring, Mr. Assouline recalled that books — at least the kind that find their resting places on coffee tables or on carefully curated and color-coordinated shelves — sold at the time for a relative pittance of $60 to $75. Mr. Assouline was quick to see an opportunity, confecting a special edition on the Indian state of Rajasthan printed on cotton and wrapped by hand in an antique sari. Its price was a then-astronomic $600, or about $2,000 today.

“It was truly a couture book,” said Robert Burke, a former Bergdorf executive turned luxury consultant who today counts Assouline among his clients. “We sold them as fast as Prosper could wrap them,” Mr. Burke recalled.

Steep prices and increasingly lavish productions seem in line with a time-tested retail axiom: At the high end of the marketplace, you are only as valued as the company you keep.

It’s a principle guiding the company even now. The Assoulines — Prosper and Martine, the French married founders, and their 30-year-old son, Alexandre — produce and sell titles, some 2,000 in the 30 years since its founding. They cover art history, fashion, interiors, travel, society, and sports.

The priciest, The Ultimate Collection — limited edition volumes, some the size of small coffee tables and bound in leather or encased in velvet or pigskin — sell in the five-figure range. A special edition on Versailles, presented in a velvet clamshell, and priced at $4,900, is offered with a private tour of the château’s interior. (The company said that The Ultimate Collection represents more than 25 percent of its annual revenues.)