Walter Martin was born in Norfolk, Virginia, in 1953. He received his B.A. from Old Dominion University in Virginia and his M.F.A. from Virginia Commonwealth University.

Paloma Muñoz was born in Madrid, Spain in 1965. She is the daughter of Spanish artist Paloma Navares.

Martin and Muñoz have been professional and personal partners since soon after they met in 1993. They live in Milford, Pennsylvania, and maintain a studio in Madrid, Spain.

Walter Martin & Paloma Muñoz are best known for their sculptures and photographs contrasting pristine settings with foreboding scenes infused with liberal doses of gallows humor. In their work, they explore the human condition, dystopias, and alienation. They focus on the multiple narratives implied in a captured moment. Their most popular works are the Travelers snow globes and large photographs. Of these, Ken Johnson wrote: "Like fairy tales or dreams, the tiny tableaus work as psychological metaphors: specifically, a stage everyone is bound to enter when life has lost its warmth and promise, at which point finding a new way becomes desperately urgent." Art critic Carlo McCormick considered their snow globes and derived photographs "a medium of futurity": "The magic here is very much about the premonitory, a way of tapping into the globe as a kind of fortune-teller's crystal ball. The cryptic misfortunes, the intimations of mortality, the panoramic tableaux of misadventure, bad luck, and wrong decisions are all ultimately a medium of futurity..."

Some of their other projects include Blind House, Spheres, and A Cure for All Remedies and Other Short Stories. Dan Cameron has complemented the artists on their ability to juggle both visual and psychological charges: "At the same time that they produce riddle-like parables about modern existence, they do not shirk the artist's obligation to invent a new formulation of tactile and even sensual pleasure."

Martin & Muñoz were commissioned in 2001 by the Arts and Design program of New York City's Metropolitan Transportation Authority to create a permanent installation for the Canal Street Station on the A, C, and E trains. Their installation, titled "A Gathering," consists of 181 black bronze birds perched throughout the station. The birds can be found on the token booth, railings, and beams throughout the mezzanine.

Aperture Foundation published a monograph of their work in 2008 with a short story written by Jonathan Lethem, who was inspired by their work. They had a retrospective at Museum der Moderne in Salzburg, which also edited a monograph of their work in 2020.