This master thesis deals with the structure of the secondary lower level of the Austrian educational system. Austrian?s children have different track options after primary education at the early age of ten years: The lower secondary school and the lower cycle of secondary academic school. The former?s major purpose is to prepare its students for working life, while the latter provides its pupils with standard entry qualifications for university. The coexistence of a comprehensive compulsory school and a selective school of choice is a unique form of school organization. At present, the secondary academic school steadily gains attractiveness, which results in increasing pupil numbers at the expense of the other school form. In urban areas the lower secondary school becomes a residual school with bad reputation, whereas in rural areas the majority of pupils decide on a lower secondary school. In addition to these issues, the impacts of differentiation policies on performance levels and several comprehensive school reforms since the 1970ies (e.g. Neue Mittelschule) are scrutinized in this thesis. For the empirical study a qualitative research method was chosen, and 15 teachers of both school types were interviewed to gain awareness which problems occur in practice. According to the teachers, the boundaries between the school forms blur and regional conditions influence the school system. A comprehensively organized school form at lower secondary level is considered an enormous project, which needs broad political support. Therefore, they take the view that the transitions and permeability of educational domains should currently be improved in order to ensure equal opportunities in education.