Jaclyn was born in 1947, in Houston, Texas. Her father Jack was a dentist and her mother was Margaret Ellen.
She attended Trinity University and the University of Texas at San Antonio.
Despite early ambitions to be a ballerina, Jaclyn turned to modelling and acting, and reached international audiences in Charlie's Angels. After being the only Angel to stay with the series for its full run, Jaclyn's career has since been primarily in made-for-TV movies.
Jaclyn has been married married and divorced three times: Roger Davis (1972-1975), Dennis Cole (1978-1981) and Anthony B. Richard (1981-1989). Since 1997, she has been married to Brad Allen, a pediatric heart surgeon.
Jaclyn has two children with Anthony: Spencer Margaret and Gaston.