Founded in 1967, the day is observed on or around Hans Christian Andersen's birthday, April 2.
Activities include writing competitions, announcements of book awards and events with authors of children's literature.
Each year a different National Section of IBBY has the opportunity to be the international sponsor of ICBD.
It decides upon a theme and invites a prominent author from the host country to write a message to the children of the world and a well-known illustrator to design a poster.
Many IBBY Sections promote ICBD through the media and organize activities in schools and public libraries.