Julie Delas works in publishing and lives near Paris. Didier Balicevic is the illustrator of numerous children's books, including many of the Ultimate Books. He lives near Paris. Robert Barborini is a graduate of L'École supérieure des arts décoratifs, where he developed his talent for sculpting and illustrating. He has illustrated many children's books, and lives in Strasbourg, France. Isabelle Jacqué is an illustrator who works for communication agencies, makes fun pictures for ready-to-wear children's clothing, and illustrates children's books. She lives near Paris. Cristian Turdera is an illustrator and designer who is known for mixing drawings and elements of collage in his work.

His work appears in magazines, books, album covers, and animated films. He lives in Buenos Aires, Argentina.