In 1985, Karen Marshall began photographing a group of teenagers in New York City. Her intent was to look at the emotional bonding that happens between girls at age 16 and document the emblematic relationships that often develop at this time in their lives. Ten months later, Molly, one of the girls in the group, was hit by a car and killed. Marshall resolved to keep the project going and continued to document the girls in various ways over the years. Between Girls evolved into a thirty-year meditation on friendship.
Karen Marshall documents social issues. She is the recipient of grants and support from private foundations. Her photographs have been exhibited internationally and are part of several collections. She is the Chair of the Documentary Practice and Visual Journalism program at The International Center of Photography in New York City.