In July, D'yan Forest celebrated her 90th birthday by performing a one-woman comedy show at Joe's Pub in Manhattan for more than 100 people. According to Guinness World Records, she is the oldest female comedian in the world.

"I always open with my age: 'I'm putting it out there right away in case I don't make it through the show,'" Ms. Forest said. "That gets them laughing no matter who's in the audience."

Before she was making people laugh, Ms. Forest was performing cabaret and playing the piano, singing mostly in French. But after the Sept. 11 attacks, she said, people stopped coming to her shows. "They went to happier places, like comedy clubs," she said.

Unable to work, she shifted gears and in 2003 hired a comedy coach. Within three weeks she was performing 10-minute sets throughout Manhattan, including at Comic Strip Live and Carolines on Broadway.

Ms. Forest grew up in Newton, Mass., and moved to a one-bedroom apartment in the West Village in 1966 after a divorce and a two-year stint "swinging and performing," she said, in Paris. All of it is recounted in her self-published memoir, "I Did It My Ways."

EARLY RISE I wake up at 7 a.m. naturally. I wish I slept longer. Being 90, I'm tired. I used to make coffee on the stove top. My building has been without gas for a year and a half, so I do it in this electric thing. Then I retrieve The New York Times from my hallway. There's a pleasure to turning the pages.