Abstract : This doctoral thesis analyses the modes of participating of young people of migrant origin, in particular those of North-African origin and of Turkish origin in today's France and Germany respectively. Especially, it deals with their educational achievements, their transition into the labour market and their forms of belonging (citizenship and elective participation). The results from French and German micro-data indicate that despite their severe difficulties in terms of school achievements, young people of Turkish origin have a more favorable working life than young people of North-African origin who are more successful in the educational system. The former experience unemployment, instability and declassing more frequently in their working life. Two types of processes of social distancing emerge from those results: through relegation in Germany and through discrimination in France. Those processes trace back to institutional, structural and symbolic mechanisms. Furthermore, both the national framework and experience of discrimination influence the forms of belonging of those population groups in different ways.