Education is compulsory from six to 18 years of age for Belgians. Among OECD countries in 2002, Belgium had the third-highest proportion of 18–21 year-olds enrolled in postsecondary education, at 42%. Though an estimated 99% of the adult population is literate, concern is rising over functional illiteracy. The Programme for International Student Assessment, coordinated by the OECD, currently ranks Belgium's education as the 19th best in the world, being significantly higher than the OECD average. Education being organised separately by each, the Flemish Community scores noticeably above the French and German-speaking Communities.
Mirroring the dual structure of the 19th-century Belgian political landscape, characterized by the Liberal and the Catholic parties, the educational system is segregated within a secular and a religious segment. The secular branch of schooling is controlled by the communities, the provinces, or the municipalities, while religious, mainly Catholic branch education, is organised by religious authorities, although subsidized and supervised by the communities
