Les écrits de septembre: New York 2001 examines the spontaneous written traces that appeared in New York after the attacks of September 11, 2001. Treating posters, messages, memorial notes, and other public inscriptions as social documents, the book explores how ordinary writing functioned in a moment of collective shock, grief, and public expression. It situates these texts within the urban space of New York and considers what their forms, placement, and circulation reveal about mourning, solidarity, and civic response. The work is valuable for readers interested in contemporary writing practices, the social life of texts, and the cultural aftermath of the September 11 attacks.