Marie Heaney was born in County Tyrone and began her teaching career in schools in Northern Ireland. She and her family moved to Dublin in 1972 where she still lives.

As well as Over Nine Waves, she has also written The Names Upon the Harp, a book of Irish legends for children, illustrated by PJ Lynch (Faber, 2000). As an editor for Townhouse Publishing in Dublin, she produced several anthologies, including Heart Mysteries, a selection of Irish poetry. In 2016, she was nominated for an Irish Book Award for her anthology All Through the Night: Night Poems and Lullabies, selected for Poetry Ireland, of which she is a patron.