Lingard has written novels for both adults and children. She is probably most famous for the teenage-aimed Kevin and Sadie series, which have sold over one million copies and have been reprinted many times since.

Her first novel Liams Daughter was an adult-orientated novel published in 1963. Her first childrens novel was The Twelfth Day of July (the first of the five Kevin and Sadie books) in 1970.

Lingard received the prestigious West German award the Buxtehuder Bulle in 1986 for Across the Barricades. Tug of War has also received great success: shortlisted for the Carnegie Medal 1989, The Federation of Childrens Book Group Award 1989, runner up in the Lancashire Childrens Book Club of the year 1990 and shortlisted for the Sheffield Book Award. In 1998, her book Tom and the Tree House won the Scottish Arts Council Childrens Book Award. Her most recent novel, What to Do About Holly was released in August 2009.

Lingard was awarded an MBE in 1998 for services to childrens literature.[
Lingard was born in Edinburgh, in the old mile but grew up in Belfast in Holland gardens where she lived until she was 18. She attended Strandtown Primary and then got a scholarship into Bloomfied Collegiate. She has three daughters and five grandchildren, and now lives in Edinburgh with her Canadian husband.