University entrance is based largely on the scores that students achieved in entrance examinations (nyūgaku shiken (入学試験)). Private institutions accounted for nearly 80% of all university enrollments in 1991, but with a few exceptions, the public national universities are the most highly regarded. This distinction had its origins in historical factors—the long years of dominance of the select imperial universities, such as Tokyo and Kyoto universities, which trained Japan’s leaders before the war—and also in differences in quality, particularly in facilities and faculty ratios. In addition, certain prestigious employers, notably the government and select large corporations, continue to restrict their hiring of new employees to graduates of the most esteemed universities. There is a close link between university background and employment opportunity. Because Japanese society places such store in academic credentials, the competition to enter the prestigious universities is keen.
Below are a list of some reputable university groups in Japan