This research proposes to study mechanisms of the transition from post-secondary schools to work and to clarify historical changes in these mechanisms accordance to the expansion of post-secondary education in the United States and Japan. The high school-work-transition has been seen as serious problems in industrial societies. However, these problems are increasingly happening to post-secondary schools. From comparative and historical perspectives, I will investigate the following questions. How do youth from different types of post-secondary institutions make the transition to work? What problems occur in their transition? How does the upgrading of youth's education alter the process of entering work? Finally, what institutional or semi-institutional linkages are involved in their post-secondary transition to work? By answering these questions, this research aims to contribute to educational and labor policies in advanced societies.