International School Ibadan was established 1963 as a joint project between the Ford Foundation and the University of Ibadan. Unlike most University secondary schools, I.S.I.’s purpose was not to accommodate University staff children but to provide standard education for expatriates and others who want world standard education for their children. In its effort to demonstrate its international outlook, the school organizes biannually what it called the International soiree, a party in which different nationalities are represented.
I.S.I. is a member of the Association of International schools. Both staff membership and studentship reflects this. While adhering to the local educational system, the school continues to prepare students for international exams such as the IGSCE too.