In 1941, Manuel Barron took the preparation guides for the New York State Regents exams (a set of standardized tests New York high school students must pass in order to get their diplomas) he'd been selling from behind the counter of a Brooklyn college bookstore and used them to launch his own publishing company. In the years since then, Barron's Educational Service has grown into a 135-employee operation with a backlist of more than 2,000 titles. The company has created study guides for all the major standardized tests and is so identified in most consumers' minds with test prep that when people meet Barron—who's still reporting for work 65 years later—they first ask if he's with "that Barron's," then talk about how his books helped them get into college. "I always get a kick out of that," he said.

But Barron's is no longer just a test-prep publisher. The company expects to add 362 books to its roster this year, and the upcoming fall season, with nearly 200 new titles, will be the biggest in its history. Study guides account for less than a third of the output, as books on arts and crafts, parenting advice, foreign languages and business management have come to dominate the list, augmented with a few gift books. "I like to say we take people from potty training to retirement, and every level of education in between," Barron said. "The one thing I've always tried to do is make Barron's the wise choice for great tips. We have a nice formula, and we have a brand name people can rely upon, so I proceed with great confidence."

Barron is quick to credit Ellen Sibley, who became the company's president and publisher in 2002, for the successful change in direction, but the company's diversification has actually been nearly four decades in the making and strongly reflects the eclectic interests of its founder. In the 1970s, for example, the publisher began a line of cookbooks after Barron studied under master chef Jacques Pepin. In some of its newer markets, such as pet care, Barron's has become as significant a player as it is in test prep. Twenty-five years ago, the company published the first in its series of Complete Pet Owner's Manuals; today it has more than 500 pet care titles in print.

Still, the company has not forgotten its roots. Barron's still offers more than 200 different titles in the study guide field, but it has faced increasingly intense competition in recent years from publishers like Kaplan's and Princeton Review. To stay competitive, Barron's has developed interactive guides for Web sites and has bundled study resources onto CD-ROMs. The company also prides itself on the thoroughness of its review material.

And though Barron has been approached several times by other publishers seeking to buy his company, he has remained firmly independent. "I like what I'm doing," he said, "and I like to do it my way. It's worked in the past, and it'll work in the present and the future."