Born in New York City on Thanksgiving Day, 1942, Marilyn Hacker was the only child of a working-class Jewish couple, each the first in their families to receive advanced degrees. She was influenced early on by her parents' hardships, especially those of her mother. Eager to excel intellectually, Hacker attended the prestigious Bronx High School of Science before enrolling at New York University at the age of fifteen. In 1964, Hacker received a B.A. in Romance Languages.
Hacker moved to London in 1970, where she worked as a book dealer. With the help and mentorship of Richard Howard, then the editor of The New American Review, Hacker's first collection of poems, Presentation Piece, was published by the Viking Press in 1974 to much acclaim. The collection was both the Lamont Poetry Selection of the Academy of American Poets and the recipient of the National Book Award.
Though she has been an outspoken lesbian since the 1970s, in 1961, Hacker married science fiction writer Samuel R. Delany, who she remained married to for thirteen years, and with whom she had one daughter.
In 1976, Hacker's second collection of poems, Separations, was published by Alfred A. Knopf, followed by Taking Notice in 1980 and Assumptions in 1985. In 1986, Hacker published Love, Death, and the Changing of the Seasons (Arbor House), a romantic narrative told mainly through sonnets. In 1990, she published Going Back to the River (Vintage Books), for which she received a Lambda Literary Award.
Hacker's 1994 collection, Winter Numbers (W. W. Norton and Company), details the loss of many of her friends to both AIDS and cancer, and explores her own struggle with breast cancer. The collection, which was in many ways darker than Hacker's previous work, won both the Lenore Marshall Poetry Prize and a Lambda Literary Award. Her Selected Poems: 1965-1990 received the 1996 Poets' Prize.
Since then, Hacker has published many more collections, including Names (W. W. Norton, 2009), Desesperanto: Poems 1999-2002 (2005); First Cities: Collected Early Poems 1960-1979 (2003); and Squares and Courtyards (2000).
About Hacker's work, the poet Jan Heller Levi has said, "I think of her magnificent virtuosity in the face of all the strictures to be silent, to name her fears and her desires, and in the process, to name ours. Let's face it, no one writes about lust and lunch like Marilyn Hacker. No one can jump around in two, sometimes even three, languages and come up with poems that speak for those of us who sometimes barely think we can even communicate in one. And certainly no one has done more, particularly in the last decade of formalism, to deomonstrate that form has nothing to do with formula. In villanelles, sestinas, and sonnets—not to mention a variety of forms whose names I can't even pronounce—Marilyn Hacker can journey us on a single page through feelings as confusing as moral certainty to feelings as potentially empowering as unrequited passion."
Hacker is also highly regarded for her criticism, editing, and translation. She served as editor of The Kenyon Review from 1990 to 1994. As translator, she has published Claire Malroux's A Long-Gone Sun (Sheep Meadow Press, 2000) and Birds and Bison (2004); Vénus Khoury-Ghata's collections Here There Was Once a Country (Oberlin College Press, 2001), She Says (Graywolf Press, 2003), and Nettles (2008); and Marie Ettiene's King of a Hundred Horsemen: Poems (Farrar, Straus and Giroux, 2008).
Hacker has received numerous honors, including the Bernard F. Conners Prize from the Paris Review, the John Masefield Memorial Award of the Poetry Society of America, and fellowships from the Guggenheim Foundation and the Ingram Merrill Foundation.
In 2008, she was elected a Chancellor of the Academy of American Poets.
She lives in New York City and Paris.