For Jack Viertel, it all began in 1954, at the Winter Garden Theatre. "When I was six, my grandmother and my parents took me to see Mary Martin in Peter Pan. I saw this audience of more than 1,000 people, including me, have this sudden outbreak of unfettered joy. I wanted to have that experience again and again - and also help create it in any way I could."

From that moment on, he was never interested in anything but theatre. "I went right home and promised all my friends that when I had my birthday party, I would make them fly."

Over the last two decades, as creative director of Jujamcyn Theaters, as a dramaturg and as artistic director of the Encores! series at City Center for the last four years, Viertel has helped many a Broadway show soar to success - including M. Butterfly, Angels in America, Smokey Joe's Cafe, Hairspray and The Piano Lesson.

Viertel's love of the stage was also inherited. A grandfather, Jack Shapiro, built the Broadway and Mark Hellinger theatres. His father, Joseph Viertel, wrote a play, So Proudly We Hail, that opened on Broadway in 1937. His older brother, Tom, is a theatrical producer. So when Jack worked on 15 plays in three years at the Pomfret School in Connecticut - and kept up his interest at Harvard - his family wasn't surprised.

After moving to California in the early 80's, he was hired as a theatre critic for a free weekly newspaper. Then he became the drama critic for The Los Angeles Herald Examiner. In 1985, Gordon Davidson, the head of the Mark Taper Forum in L.A, made him the theatre's dramaturg. Two years later, Rocco Landesman, then the new president of Jujamcyn, which owns five Broadway theatres, remembered Viertel from a review he had written of Landesman's musical Big River and decided to hire him. "It's my job," Viertel says, "to help figure out what should be in the theatres, and, where we're also the producers, to work with the writer and director to help make the play or musical as strong as it can be." His first play with Jujamcyn was David Henry Hwang's M. Butterfly, "which I brought with me from California in my suitcase." It won the Tony Award for Best Play in 1988.

Viertel was the dramaturg for Hairspray. "The art of dramaturgy is the art of asking questions about things you don't understand. Sometimes it's not clear why things happen in a certain way or whether a character is developing logically, and by asking questions you can help clarify a play or a musical or help invent new material that makes a work better."

In 2001, Viertel was named artistic director of Encores!, which presents three vintage Broadway musicals each season. "It's not so much finding shows we want to do - there are lots. It's finding a season, with musicals from different eras, to combine wonderfully familiar theatre music and something that might stretch the audience, something they're not expecting."

Viertel has also written the book of a musical - Time and Again, a tale of time travel presented at the Manhattan Theatre Club four years ago. He'd like to be a librettist again. After all, he says, there's always the hope of another "sudden outbreak of unfettered joy."