Soon after college China formed and sang with her first band. They regularly performed at NYC clubs CBGB's Gallery, Mercury Lounge and Brownies. Her first solo album Love Handle was released in 1995 and she was chosen to sing "Ordinary Girl," the theme song to the TV show Clueless.
In 1995, she was plucked from New York City by Harvard classmate Thomas Lauderdale to sing with Pink Martini, and has since written many of Pink Martini's most beloved songs with Lauderdale, including "Sympathique," "Lilly," "Clementine," "Let's Never Stop Falling in Love," "Over the Valley" and "A Snowglobe Christmas," which can be heard on Pink Martini's holiday album Joy to the World. Her original song "Hey Eugene" is the title track of Pink Martini's third album and many of her songs can also be heard on television and film. She sang "Qué Será Será" over the opening and closing credits of Jane Campion's film In the Cut and her original song "The Northern Line" appears at the end of sister Maya Forbes' directorial debut Infinitely Polar Bear, which was released in 2015 by Sony Pictures Classics.
With Pink Martini, Forbes has appeared on The Late Show with David Letterman, Late Night with Conan O'Brien, The Tonight Show with Jay Leno and Later with Jools Holland. She has performed songs in over twenty languages and has sung duets with Michael Feinstein, Jimmy Scott, Georges Moustaki, Henri Salvador, Saori Yuki, Faith Prince, Carol Channing and Rufus Wainwright among others. She has performed in venues from Carnegie Hall to Red Rocks, the Sydney Opera House to the Grand Rex in Paris. She released her second solo album '78 on Heinz Records in 2008, a collection of autobiographical folk-rock songs.