Libby Hathorn writes poetry, picture books, libretti, scripts, educational resources and young adult novels. She has lived in Sydney since she was two years old. She studied at Sydney Girls High School, Sydney University and Sydney Technical College, before completing her training at Balmain Teachers College.

She worked as a primary school librarian in the inner city for ten years, during which time she began her writing for children with 'ideas' kits for teachers, and the picture book texts for Stephen's Tree (1979; illustrated by Sandra Laroche) and Lachlan's Walk (1980, illustrated by Sandra Laroche). In 1981 she moved to adult education, working as a scriptwriter, producer and director for educational films and television. She continued to write for children, with growing critical success. The Tram to Bondi Beach (1981, illustrated by Julie Vivas) was Highly Commended in the 1982 Children's Book Council of Australia (CBCA) Picture Book of the Year Awards. Her later books have continued that success. Among her many awards are the Asher Literary Award, multiple Biennial Book Awards, and an AWGIE Award for her adaptation of her own Grandma's Shoes.

In 1987, Hathorn received a grant from the Australia Council, enabling her to work full-time on the first of her young adult novels, Thunderwith (1989). This novel was also a CBCA Honour Book, was translated into several languages, and later made into a telemovie (renamed The Echo of Thunder).

Poetry is Hathorn's first love, and she sees similar qualities in poetry writing and writing for children, such as succinctness, controlled language, strong imagery, surprise, and the ability to move the reader.

Contemporary settings and universal themes are elements Hathorn uses in her writing; perhaps most strongly demonstrated with her picture book for older readers, Way Home (1994, illustrated by Gregory Rogers, the first Australian to be awarded the Kate Greenaway Medal for his artwork). This tale of a street kid created controversy when it was first published, with some claiming it was hardboiled, and others that it romanticised the plight of the homeless. Many of Hathorn's books have been translated and been published internationally, as well as adapted for the stage.

Hathorn has lectured part-time in Creative Writing at the University of Sydney. She is the director of Hathorn Enterprises.