Swiss vocational education and training (VET) at upper secondary level is characterised by strong vertical stratification. Academically demanding programmes with high potential regarding further education and labour market careers contrast with academically modest programmes of restricted potential. To date, there is little research available on the selection mechanisms at work when youths strive to access this stratified system, as little as on the effects of these VET programmes with regard to subsequent education and labour market careers. Drawing on the Swiss longitudinal TREE data set, this contribution first models VET entry selection depending on the volume of its academic programme at vocational school. In a second step and by means of a matching procedure, we estimate the effects of these programmes on the subsequent education and labour market careers. Our findings highlight that VET entry is shaped by strong institutional channelling, a relatively weak influence of student achievement, but a strong impact of social origin. The analysis of effects on subsequent careers shows that, all else being equal, trainees of VET programmes with poorly equipped academic curricula are confronted with substantially reduced odds to complete tertiary education, as well as significantly restricted opportunities on the labour market.