Grace Mayer was an American museum curator, photography historian, and advocate whose pioneering work helped establish photography as an important area of museum collecting and exhibition in the United States. Best known for her long career at the Museum of the City of New York, Mayer played a crucial role in preserving photographic history and promoting the recognition of photography as both an artistic medium and an invaluable historical record. Through her curatorial vision, scholarly research, and dedication to expanding museum collections, she became one of the most influential museum professionals in the field of photography during the twentieth century.