Grassé began publishing a very big project in 1946 entitled "Traité de zoologie". The 38 volumes required almost forty years of work, uniting some of the greatest names in zoology. They are still essential references in the field for the groups that are treated in their pages. Ten volumes are dedicated to mammals, nine to insects. Apart from this treatise, he led two collections published by Masson: the first, entitled "Grands problèmes de la biologie", has thirteen volumes and the second is entitled "Précis de sciences biologiques". Alongside Andrée Tétry, he composed the two volumes dedicated to zoology in the collection "Bibliothèque de la Pléiade", published by Gallimard. He also supervised the edition of the "Abrégé de zoologie" (two volumes, Masson).