Marlow studied psychology at Manchester University, graduating in 1974. He began his photography career in 1975 working on an Italian cruise liner in the Caribbean before joining the Sygma news agency in Paris in 1976. In the late 1970s Marlow worked in Northern Ireland and Lebanon, but soon found that the competition of photojournalism did not suit him. He returned home to Britain, and worked in Liverpool on an 8-year project. He became associated with Magnum photos in 1981 and became a full member in 1986.
In 1991 he received an assignment from the Somme department in France to photograph Amiens. Later he began to work abroad again, travelling to Japan, the United States, and other parts of Europe. His photography now is primarily in color. Though well known for his depictions of places, Marlow has also documented politics with a collaboration with Tony Blair.
Département Somme: regards de photographes. Amiens: Trois Cailloux, 1992. ISBN 2903082669. Photographs by Marlow, Harry Gruyaert, Jeanloup Sieff, Michel Vanden Eeckhoudt, Martine Voyeux and Hugues de Wurstemberger; prefaces by Christian Caujolle and Jacques Darras.
Europe on the dark side of the stars. France: Secours Populaire Francais, 1992.