Katherine Lahusen (also known as Kay Tobin; January 5, 1930 – May 26, 2021) was an American photographer, writer and gay rights activist. She was the first openly lesbian American photojournalist. Under Lahusen's art direction, photographs of lesbians appeared on the cover of The Ladder for the first time. It was one of many projects she undertook with partner Barbara Gittings, who was then The Ladder's editor. As an activist, Lahusen was involved with the founding of the Gay Activists Alliance (GAA) in 1970 and the removal of homosexuality from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM). She contributed writing and photographs to a New York–based Gay Newsweekly, and co-authored two books: The Gay Crusaders in 1972 with Randy Wicker (