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 Liam's Daughter was an adult-orientated novel published in 1963. Her first children's 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 Children's Book Group Award 1989, runner up in the Lancashire Children's 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 Children's 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 children's 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.

Adult novels

• Liam's Daughter (1963)
• The Prevailing Wind (1964)
• The Tide Comes In (1966)
• The Headmaster (1967)
• A Sort of Freedom (1968)
• The Lord On Our Side (1970)
• The Second Flowering of Emily Mountjoy (1979)
• Greenyards (1981)
• Sisters by Rite (1984)
• Reasonable Doubts (1986)
• The Women's House (1989)
• After Colette (1993)
• Dreams of Love and Modest Glory (1995)
• The Kiss (2002)
• Encarnita's Journey (2005)
• After You've Gone (2007)

Children's novels

• The Twelfth Day of July (1970)
• Frying as Usual (1971)
• Across the Barricades (1972)
• The Clearance (1973)
• Into Exile (1973)
• A Proper Place (1975)
• The Resettling (1975)
• Hostages to Fortune (1976)
• The Pilgrimage (1976)
• The Reunion (1977)
• Snake Among the Sunflowers (1977)
• The Gooseberry (1978)
• The File on Fraulein Berg (1980)
• Strangers in the House (1981)
• The Winter Visitor (1983)
• The Freedom Machine (1986)
• The Gulity Party (1987)
• Rags and Riches (1988)
• Tug of War (1989)
• Glad Rags (1990)
• Can You Find Sammy the Hamster? (1990)
• Between Two Worlds (1991)
• Morag and the Lamb (1991)
• Secrets and Surprises (1991)
• Hands Off Our School (1992)
• Night Fires (1993)
• Clever Clive and Loopy Lucy (1993)
• Slow Flo and Boomerang Bill (1994)
• Sulky Suzy and Jittery Jack (1995)
• Lizzie's Leaving (1995)
• Dark Shadows (1998)
• Tom and the Tree House (1998)
• A Secret Place (1998)
• The Egg Thieves (1999)
• Natasha's Will (2000)
• River Eyes (2000)
• Odd Girl Out (2000) (re-issue of The Gooseberry)
• Me and My Shadow (2001)
• Tortoise Trouble (2002)
• Tell the Moon to Come Out (2003)
• The Sign of the Black Dagger (2005)
• The Eleventh Orphan (2006)
• The File on Fraulein Berg (2008)
• What to Do About Holly (2009)