Heather O'Neill is a Canadian novelist, poet, short story writer, screenwriter, and journalist. She published her debut novel, Lullabies for Little Criminals, in 2006. The novel was subsequently selected for the 2007 edition of Canada Reads, where it was championed by singer-songwriter John K. Samson and won the competition. The book also won the Hugh MacLennan Prize for Fiction and was shortlisted for eight other major awards, including the Orange Prize for Fiction and the Governor General's Award. It was longlisted for the International Dublin Literary Award.

Lullabies for Little Criminals became an international bestseller, making Heather one of the most influential women in Canada according to Chatelaine magazine. Her other works include The Girl Who Was Saturday Night (2014) and Daydreams of Angels (2015), both shortlisted for the Giller Prize. Her third novel The Lonely Hearts Hotel was published in February 2017. Heather O'Neill has also written a screenplay, a book of poetry, and contributed to publications such as The New York Times Magazine, This American Life, and The Globe and Mail.