I was talking to John Fernandez who heads up the AACSB recently, and he said that he estimates that there are over 8,000 "business schools" worldwide of which perhaps about six or seven hundred are accredited by major accreditation groups. The popular rankings concentrate on, at most, the top one hundred schools, or less than 2% of all the schools. It is obvious therefore that the vast majority of business school students in the world have little comparative and independent evaluations of their schools, certainly far less than is readily available for those that are ranked. When looked at in this perspective, the current system gives a great deal of information for a small percentage of schools with neither accreditations nor the rankings having much to say about the vast majority of schools.
The top business schools will continue to command attention from the press and from accreditation agencies, but the massive and growing numbers of other schools will command attention too and their sheer numbers will make them more and more important in the future.