Louis Constantin, a graphic designer and illustrator known for his pivotal role in defining the visual identity of the French book collection Biblio, has died at the age of 66. He first gained recognition in 1982 after participating in an international competition organized by Hachette to redesign the look of Le Livre de Poche, a well-known French publishing imprint. Although his proposal did not win the top prize, it inspired the creation of the Biblio collection, which was later launched under the direction of Jean-Claude Brisville. This collection became a significant part of French publishing, known for its distinctive and modern design. Throughout his career, Constantin worked with several publishers, including Hachette and L'Asiathèque, creating illustrations and layouts for a wide range of books. His work on Biblio included the cover of Mr. North by Thornton Wilder, and his illustrations appeared across various sections of Hachette and Le Livre de Poche, including youth literature such as Contes de la Bécasse by Guy de Maupassant, published by Hachette Jeunesse in 1994. His designs often combined simplicity with a strong visual impact, making them instantly recognizable. In addition to book covers, Constantin collaborated with poet Jean-Luc Moreau on Déninettes, a 1991 book published in the Fleurs d'encre collection. The book was notable for its unique blend of text and image, designed to encourage an interactive reading experience. A later version, Donne ta langue au chat, was published in 2005 by Gautier-Languereau as part of the Enfance est poésie collection, continuing the tradition of blending visual and literary elements. Constantin also had a long-standing relationship with L'Asiathèque, a publishing house focused on multilingual literature. His work with the company included the Bilingues collection, which features original texts alongside their French translations. This collection has featured works in a wide range of languages, including Arabic, Greek, Quechua, Korean, Hungarian, Turkish, Kyrgyz, Persian, and Chinese. His illustrations have continued to be used in reprints from the 2000s and 2010s, showing the lasting influence of his work in the world of publishing.