Approaching Daniel Handler with a proposal to personalize his intensely ironic Lemony Snicket books might sound a little like sticking your head into the mouth of his Incredibly Deadly Viper. But — fortunately for all involved — Handler was intrigued by the idea of adding children's names and photos to his "All the Wrong Questions" books.

"To me, it spoke to the personalized experience of reading," he said.

"The majority of letters that I get from my readers are in some way trying to play along or inhabit the world of the books. They don't ask me what kind of car do I drive, or where do I get my ideas. They're more likely to say 'I saw Count Olaf hiding behind this bush,' or I'm very worried about Ellington Feint.' "

Handler is the latest addition to a list of creative heavy-hitters who have signed on to produce personalized books with Sourcebooks, a publisher that launched its personalized Put Me in the Story division in 2013. Sesame Street and Disney — the princess powerhouse and the "Star Wars" subsidiary — have partnered with Sourcebooks to produce personalized books, as has Nancy Tillman, author of the bestseller "On the Night You Were Born."

For writers and publishers eager to connect with kids, the potential rewards are tremendous, but so, too, are the challenges. How do you personalize a book in a way that's fully satisfying to children and parents — and at the same time fully respectful of original text or character? How do you give parents and grandparents room to be creative without giving authors high blood pressure?

How do you satisfy the tween Lemony Snicket reader's need for connection without introducing even a whiff of (eyeroll-inducing) condescension?

Sourcebooks' Karen Shapiro, leader of a creative team that works closely with editors and designers, said the process begins with a "deep dive" into the book.

"You have to understand what the author's intent was, what the audience was expecting from the author. You don't invade that story or disrupt it in any way; you want to enhance the experience," said Shapiro, publishing manager of the Sourcebooks entertainment and gift group.

That might mean never touching the actual text or illustrations; in "On the Night You Were Born," the child's name is softly threaded through blank spaces. Or it could mean repeatedly adding a name and photo to text and illustrations, as in the case of Sandra Magsamen's "You!" Even the same author can get very different treatment from book to book; the personalization is minimal in Magsamen's "Welcome Little One," which celebrates the arrival of a new baby.

"It was such a beginning of life — a new baby being born," Magsamen said. "I felt that was the right touch, to gently have the child be part of the book, but also be a part of what the mom or the dad or the grandparent wants to share with the child."

The book includes space to write in information about the newborn, including time of birth, weight and length. There's also a dedication page with a personal message printed by Sourcebooks and a picture of the baby.

Sourcebooks' personalized books have sold hundreds of thousands of copies, said publisher and CEO Dominique Raccah.

Handler, whose four-book "All the Wrong Questions" series has been published in personalizable form, said the Lemony Snicket books are particularly well-suited to this kind of customization because the title character addresses the reader in frequent asides.

He added 13 letters to would-be members of the daring VFD, interspersing them throughout the four books. The letters are addressed to the child, and some make reference to the book-giver. The letters include quizzes, instructions and delectable dry asides.

In addition, the child's name appears (more than once — look carefully) on the cover of the book. And the child's photo is inserted in a gallery of character images drawn by the series' illustrator, Seth.

It's easy to imagine ways customization could go wrong: Sticking a kid's name into a novel could interrupt flow, alienate sophisticated young readers and make authors run for the hills. Handler, who is famous for imagining terrible worst-case scenarios in the case of his unlucky Baudelaire orphans, offered a Snicket-worthy response when he was asked about these potential dangers.

"I've been alienating readers one way or another my entire life," he said. "As someone who feels alienated all the time I have nothing but sympathy for people who are feeling alienated, but I can't worry about it. I'm worried about my own alienation. That's how I spend my day."