Aird was born in Huddersfield, West Riding of Yorkshire in England. She attended the Waverley School and Greenhead High School, both in Huddersfield. As a young adult, she was bedridden due to a serious illness.[3] Upon recovery, she worked as practice manager and dispenser for her father's medical practice in Sturry, near Canterbury, Kent.[4]
Her first novel, The Religious Body, was published in 1966.[2] Aird is best known for her successful Chronicles of Calleshire, a series of crime novels set in the fictional County of Calleshire, England, and featuring Detective Inspector C.D. Sloan of the Berebury CID, and his assistant, Detective Constable Crosby.[2] She has also written and edited a series of village histories, and is an editor and contributing author on works regarding other writers and the art of writing.
Aird served as Chair of the Crime Writers' Association from 1990 through 1991. She has been awarded the CWA Golden Handcuffs award for lifetime achievement and the Diamond Dagger for an outstanding lifetime's contribution to the genre, in 2015.