Ann Rae Rule (née Stackhouse; October 22, 1931 – July 26, 2015) was a celebrated American author known for her compelling true crime books and articles. She gained widespread fame with her book The Stranger Beside Me (1980), which details her experiences with serial killer Ted Bundy, who was once her co-worker and friend. This unique perspective distinguished her in the genre of true crime writing.

Ann Rule authored over 30 true crime books including Small Sacrifices, about Oregon child murderer Diane Downs. Many of her works focus on murder cases in the Pacific Northwest and her adopted home state of Washington.

Raised in a law enforcement and criminal justice environment, Rule initially aspired to work in law enforcement. She was a former Seattle Policewoman and was well-educated in psychology and criminology. Her first book, The Stranger Beside Me, was being researched while the Ted Bundy murders were still unsolved, giving her work a uniquely personal and insightful edge.

In recognition of her contributions, Ann Rule won two Anthony Awards from Bouchercon, the mystery fans' organization.