In this thesis an attempt is made to explain the decisive grounds on which the choices of education and work are made. The precise question at issue is; Why does one choose the industrial-technical course of study in upper secondary school? Thus a special interest is taken in the practical vocational training. At the present time the social segregation in upper secondary school is almost as prevalent as it was in the former system based on separated types of theoretical and practical educations. Nor has the social mobility increased to any appreciable extent during the postwar period despite reorganization of school with an explicit democratic aim. The structural changes of the Swedish society during the post-war period have first and foremost affected the middle-class. The social segregation in upper secondary school cannot be explained from an individual point of view, where each individual represents a sovereign subject who "freely chooses" his or her education and work-future. In the thesis this matter of conditions is explained, instead, from a structural and phenomenological starting point. Within sociology of education the cultural and social reproduction represented in the choice of education and work is considered to be an effect of the way in which such social institutions as school, family and work are functioning in our type of modem society. By a theoretical reconstruction of the Swedish society during the 20th century, seen from the three most essential elements of social structure, namely school, work and family, one may "understand" the decisive grounds for choosing education and work. The tools of the analysis represented by the work of reconstruction have been the concepts of epistemology, field, economic- and cultural capital, respectively and politics. The work of the first part of this thesis, with the subtitle: History and Structure, has as a result a sorting out of a number of conjunctures where epistemology and politics have coincided in Swedish society. The essential one of these conjunctures is made up by the period of society from 1930-80, known as the Swedish Model. The results of this historical and structural analysis of the Swedish society during the 20th century make it possible to understand the social operations which lie behind the "choice" of education and work - and thus in a new way answering the problems at issue of this thesis. In the second part of the thesis with the subtitle: Interpretation, the conclusions of the first part are put into practice. The basis here is the period after the Swedish model, i.e. from about 1980 till the present day. In this part I show the results of a study made on a school-class in the industrialtechnical course in an upper secondary school in Gothenburgh. By combining interpretation and application of the results 1 explain why young people "choose" the industrial-technical course of study in upper secondary school.