Nearly a decade ago, there was considerable debate among Princeton residents about whether the Princeton Public Library should rebuild on its Witherspoon Street corner site or relocate to Princeton Shopping Center. Betty Wold Johnson, one of the library’s most generous supporters, was all for the latter option.

“I didn’t want it in Princeton at all,” Mrs. Johnson recalled last week during a telephone conversation. “In the shopping center, [where the library relocated during its rebuild] I could go to the library and do my shopping at the same time. I thought it would have been just great.”

The library stayed on its corner footprint, replacing its 1966 structure with a state-of-the-art building that has become one of the busiest public libraries in New Jersey. And Mrs. Johnson soon came around to the idea. Starting with a $1 million gift for the capital campaign, she has since donated challenge grants for the endowment campaign of $2 million. Her latest is another $1 million in challenge grant funds, to build a new endowment for maintenance and upkeep of the building, now eight years old.

“The most important thing about Betty Johnson is that she is quietly philanthropic, in a way that has significantly changed not just Princeton Public Library, but many organizations,” said Leslie Burger, PPL’s director. “She is very unassuming. She asks incredibly smart questions. What she has done has been quietly transformational.”

In recognition of her staunch support, Mrs. Johnson is the honorary chair of “Beyond Words,” this year’s fundraiser for Friends of the Princeton Public Library. Pulitzer Prize-winning author Jeffrey Eugenides is the featured speaker at the Saturday, September 29 event, which begins with his talk at Richardson Auditorium and follows with a cocktail reception, silent auction, and dinner in the library.

The widow of Johnson & Johnson heir Robert Wood Johnson III [and later Douglas Bushnell], Mrs. Johnson first began contributing to the library in the early 1990’s. “She started in 1991 to support the attempt to keep the library open during Sundays and some holidays,” Mr. Burger said. “She provided that support for many years.”

Ms. Burger isn’t sure just how, when, or why Mrs. Johnson became an advocate for rebuilding the library on its existing footprint. But once she made the switch, she was firmly committed.

“Betty was a doubter,” Ms. Burger said. “She wanted the library to stay at the shopping center. But for whatever reason, she was here the day we were moving the books in. I put a hard hat on her and said, ‘Here, let’s get to work.’ And she jumped right in.”

Mrs. Johnson remembers the day well. “I happened to be there that first day that the books came in,” she said. “Leslie handed me a dust rag and we got to work. That’s also the day I found out she baked cookies, because she had brought them in for everyone.

“This is how I’ve come to know Leslie,” Mrs. Johnson continued during a phone interview, proceeding to read something she had written about Ms. Burger. “When Leslie Burger came to Princeton to our library, we didn’t know what we were getting. It wasn’t long before we discovered we had hired a cleaning lady who baked cookies for workers, an arranger of books and a mover of furniture, and an accountant who notices when the water bill goes up. She’s our CEO and beloved librarian.”

Donations from Mrs. Johnson to the library come from two sources: the Robert Wood Johnson 1962 Charitable Trust, and the Williard T.C. Johnson Foundation Inc. There are three areas of the library named for Mrs. Johnson: the Teen Center, the Terrace Garden, and the Afterschool Study Center.

“Her gifts to the centennial campaign were instrumental in helping us reach our goal of $10 million,” said Ms. Burger. “She is a huge library supporter. We couldn’t be where we are without her.”