Nancy Lefenfeld has, over the past two decades, conducted research on the subject of humanitarian resistance in France during the Shoah and has spoken and written extensively on the subject. A French translation of her work on the smuggling of Jewish children from France into Switzerland was published under the title Le Sort des Autres: Le sauvetage des enfants juifs à la frontière franco-suisse (L’Harmattan, 2016). She authored a chapter in Jewish Resistance Against the Nazis, edited by Patrick Henry (The Catholic University of America Press, 2014), and her articles have appeared in The Hidden Child and Prism: An Interdisciplinary Journal for Holocaust Educators.