Sarah Dessen was worried when her agent told her that her first book, That Summer, was a “young-adult novel.”

At the time, there was little to bridge the gap between children’s and adult fiction beyond such series books as Sweet Valley High, and Dessen feared her teen-focused novel would be shelved with such kiddie staples as Goodnight Moon and Beverly Cleary’s Ramona Quimby series.

“I was worried about the stigma of it, which was stupid,” Dessen says.

The Chapel Hill native needn’t have worried. Ten years and eight books later, more than 1.5 million copies of her books exist in print, and in 2003, two of her YA novels were adapted into the Mandy Moore film How to Deal. Her last book, Just Listen, spent 18 consecutive weeks on the New York Times‘ bestseller list, and Lock and Key, her eighth novel, published by Viking Juvenile, is poised to follow in its success.

Dessen’s books often deal with teenage girls going through an upheaval in their lives, and Key is no exception. The narrator, Ruby, living alone since being abandoned by her mother, is made to go live with her estranged sister and her ultra-wealthy husband. “If you look at the trend in YA fiction right now, a lot of it is about girls who find out they’re princesses or girls who suddenly become celebrities,” Dessen says. “So I was interested in seeing what happened if you were living this very hardscrabble existence, and struggling a lot, and suddenly you were plunged into this world of affluence and money and private school, and what if you didn’t like it?”

Key has its roots in Dessen’s life in Chapel Hill, where she still lives. “I used to live in a little farmhouse off the Chapel Hill side of Durham, where I lived with my husband right after college,” Dessen says. Though she was glad to move out of the house, she maintained affection for itwhich made it all the harder when she drove by a few years ago to find out the entire property had been razed for an upscale community. “There’s a big, terracotta-looking wall there now and these very big mansions behind it and a gate you have to go through to get to the houses,” Dessen says.

Chapel Hill has always been present in Dessen’s work, most explicitly in an early, unfinished novel, written while in college at UNC (where both her parents taught). In that effort, which Dessen claims was “horrible,” she didn’t bother to disguise the town’s identity.

“People in my writing group kept pointing out the inaccuraciesit would take longer to get from the hospital to the airport than thatbecause everyone has an opinion on a place they already know,” Dessen says with a laugh. Still, the area has not only influenced the setting of her books, but also lets her easily flash back to her own high school experiences. “I tend to drive past a lot of places where things happened to me in high school, so I’m never too far away from it,” Dessen says.

Though the birth of her first child has slowed things down, Dessen is already at work on her ninth novel, along with promoting Key. And while young adult books are now huge, Dessen notes she was there before the trend started and will try to be there after it’s over. “It’s a great time to be in young adult right now,” Dessen says. “It’s an amazing world, and there are so many great people writing in it.”

Sarah Dessen has two upcoming local appearances in support of Lock and Key: 3 p.m. Saturday, May 3, at Quail Ridge Books and Music in Raleigh, and 2 p.m. Sunday, May 18, at McIntyre’s Fine Books in Fearrington Village. Dessen maintains a blog at writergrl.livejournal.com.