Japanese education is made up of two sectors – school education and shadow education. Although the school system is always discussed officially, shadow education, which is usually called juku in Japanese, has rarely been discussed officially or studied academically. However, the latter has really earned trust from people and it is no exaggeration to say that the jukus have sustained the academic performance of Japanese people in the post-war[i] period. And owing to this dual structure, Japanese education can be considered a huge experimental field for education policies, systems, and methods. Therefore, I would like to draw the attention of researchers and policymakers who are interested in sociology of education, privatization of education, and education in the information age, etc. In particular, I would like to give a brief outline of the background in which the juku industry emerged.