American author of fiction for adults and young adults, she is best known as the creator of the Gallagher Girls series. Her other works include the Heist Society series and a novella entitled Double-Crossed.
She received degrees from Oklahoma State University and Cornell University. Her first published works were Cheating at Solitaire and its 2006 sequel, Learning to Play Gin.
Cross My Heart and Hope to Die, her sequel to I'd Tell You I Love You, But Then I'd Have to Kill You, debuted in 2007 and spent ten weeks on The New York Times Best Seller list.
She was born Sarah Leigh Fogleman, but chose the pen name of Ally Carter so her books would be placed near those of adult-fiction writer Jenny Crusie. She grew up in Oklahoma with an older sister.
She is a contemporary of Jeff Kinney.