Theresa Weir (born 1954), better known by her pen name Anne Frasier, is an American author of numerous genres.

Anne Frasier was born in Burlington, Iowa and attended Artesia High School in Artesia, New Mexico. Her parents divorced when she was six years old. The next twelve years of her life were spent in poverty, moving to and from Florida, Iowa, California, Illinois, and New Mexico. After graduating she worked as a waitress, a factory worker at Albuquerque's Levi Strauss where she sewed the Levi's logo on the back pockets of jeans, followed by a secretarial position at Wally's LP Gas in Santa Fe, New Mexico. She has started writing in her early twenties.

At age 21 she married her late husband whom she had met while working at her uncle's bar in Illinois. After marrying, she and her husband, who had a background in agriculture, moved to an apple farm. In an interview with Huffpost Frasier stated how "[she] had this idealized notion of getting back to nature and the land. I imagined myself barefoot with a baby on my hip, raising crops and canning organic vegetables." However, she soon grew dispirited due to the ill effects of pesticides and the helplessness she experienced because of her inability to "[...] do anything about it".

Frasier credits these negative feelings, as well as general isolation, as the spark that prompted her to start writing genre fiction. As an unpublished author without college education, she did not know anything about submitting manuscripts. According to Frasier, she began mailing manuscripts to publishing house addresses she found in books. Her first sale was to the American publishing company Simon & Schuster; The Forever Man was published on April 28, 1988, by the Silhouette Book Publishing Division of Simon & Schuster, which specialised in romance novels. The Forever Man, which was published under the name Theresa Weir, is now out-of-print and has been removed from her bibliography on her official website, annefrasier.com.

After writing fiction spanning numerous genres for over 20 decades, she textualised her experience of American farm life during the 1980s in her memoir The Orchard. Additionally, her second memoir The Man Who Left chronicles her strained relationship to her father, who had left the family when she was five years old and later developed Alzheimers.

As of 2022, Frasier lives in Southern California with her dog and frequently shares insights into her personal life as well as her stance on environmentalism via Instagram. She has previously stated that she is "addicted" to Facebook and Instagram.

Since the publication of her first novel, The Forever Man in 1988, Frasier has written over 40 novels, novellas, short stories, and anthologies under both her real name, Theresa Weir, as well as her more commonly used pseudonym Anne Frasier. During her early career Frasier wrote exclusively under the name Theresa Weir and specialised in romance novels, such as her 1988 novel Amazon Lily, which won the Romantic Times Best New Adventure Writer Award and was a RITA finalist.

In the year 2002 her novel Hush was published. This was the first instance of her using the pen name Anne Frasier.