The aim of this thesis is to examine the ways in which the institutional identities of four private schools in Attiki are presented through their websites, as well as the ways in which the concept of discipline emerges in their posted regulations. This inquiry is theoretically supported by the New Institutional Sociology, in terms of institutional identities and the work of Michel Foucault,  regarding the concepts of discipline and power. The sample of the research were the websites and mainly the posted regulations of the four private schools. Qualitative Content Analysis was used to analyse school regulations while Critical Discourse Analysis was used to clarify the concepts of excellence and innovation. This research concludes that there is isomorphism among the four schools concerning theemphasis on the history of each school and the context of its establishment, parents’ acceptance regulations as prerequisite for attendance and attention to tradition and innovation. The concept of discipline is linked to school principles, family-school relationships and the role of space and time in school practices. At the same time, the differences in institutional identities concern the concept of excellence, the creation of a family atmosphere, the Christian character of the school and in its charitable activity.