Modern Spiritual Masters is a 11-book series with 11 primary works first released in 1970 with contributions by Mahatma Gandhi, Henri J.M. Nouwen, Pierre Teilhard de Chardin, Thich Nhat Hanh, Edith Stein, John Sullivan, Alfred Delp, Thomas Merton, Dorothee Sölle, Etty Hillesum, Dom Helder Camara, Tim Flinders, and Mary Evelyn Tucker.