Institutional Determinism such as ‘oversocialized’ individuals (Tolbert and Zucker, 1996, pp. 176) regards institution as fixed. Strategic Constructionism such as ability of make rules (Pfeffer and Salancik, 1978, pp. 49) regards institution as not fixed and changeable. This paper argues integrating these two contradicting concepts of institution. Berger and Luckmann (1966) discuss the process of constructing institutions, and conclude that social order is an ongoing human product. Institution can never be fixed. However, as DiMaggio and Powell (1983) argue, isomorphism occurs under the pressure of an institution as if it was fixed and De Facto. Examining the history of the Japanese commercial key TV stations in Tokyo and the principle of excluding multiple ownership of the media, it is clear that any institutions were never fixed, but, for some periods, looked fixed because the firms complied with the institutions, and isomorphism occurred among the stations. Though there have been always ongoing interactions between the firms and the institutions.