Dame Marie Mildred Clay DBE FRSNZ (/məˈriː/; née Irwin; 3 January 1926 – 13 April 2007) was a researcher from New Zealand known for her work in educational literacy. She was committed to the idea that children who struggle to learn to read and write can be helped with early intervention. A clinical psychologist, she developed the Reading Recovery intervention programme in New Zealand and expanded it worldwide.