Description: Educational restructuring is an international phenomenon which emphasises a voucher system, upper secondary schools' local decision-making and pupils' choices in contrast to previous bureaucratic governing. For this reason upper secondary programmes and courses on offer, together with the pupils' individual choices, have a direct impact on what could be called the upper-secondary education market. In terms of teaching subject matter, upper secondary education is, at the same time, broadened by means of introducing three-year programmes for all pupils as well as core subjects. The aim of this paper is to develop a deeper understanding of how pupils' actions of choice create different sorts of integration and differentiation processes within the restructured upper secondary education. Methodology: Young people's' choice of education has traditionally been studied in connection with their choice of upper secondary school or upper secondary programme. Other studies' clearly defined aim has been the analysis of different pupil categories and their choice of courses within upper secondary school. Analyses limited to the school subject Swedish in upper secondary education have also been made. The focus of these studies was to discuss the integration and differentiation processes of the subject Swedish in upper secondary education. For this thesis, interviews with twenty-two pupils were repeatedly conducted. The pupils were in their last term at compulsory school when they were interviewed for the first time; they were interviewed for the last time after completion of their first year in upper secondary education. The purpose of such an empirical design is to study pupils' successive actions of choice over time. The interviews were about pupils' ways of handling situations and contexts which, in one way or another, had to do with their development of knowledge and social relations in the sense of pedagogical practices. In the light of Jürgen Habermas' theory of communicative action combined with Norman Fairclough's critical discourse analysis, pupils' actions of choice have been studied within four pedagogical practices: (i) choice of upper secondary school, (ii) choice of upper secondary programme, (iii) pupils' initial time at an upper secondary school and how they cope with the specific culture within a programme as well as choice of courses and subjects, and (iv) pupils' own stories and points of view on how a core subject, namely Swedish, was taught. Conclusions: The results demonstrate that pupils' actions of choice can be vocation-oriented, career-oriented and consumption-oriented. It is argued that these different types of actions of choice are constituted within a market discourse. The market discourse demands that pupils are able to make suitable choices to achieve an individualistic qualification. From that point of view upper secondary education's integration and differentiation processes aim at developing citizens' personal opportunities in order for them to benefit to their best ability from what society has to offer. Other results demonstrate that pupils' group-oriented, interest-oriented and tradition-oriented actions of choice are built upon another type of discourse, which is about educating pupils towards active citizenship. It has an inter-subjective point of departure. Pupils are driven into the integration and differentiation process where they discuss and take a stand in favour of those educational options, which are conceived as the most relevant in relation to a "self-determining ethical-cultural community". The analysis of these two dominant discourses indicates that pupils' integration and differentiation processes are ambiguous.