In this dissertation I investigate the role played by institutions in the development of employability of disadvantaged young people. An original theoretical framework informed by the Capability Approach and the Transitional Labour Markets Approach accounts for both individual and institutional perspective and is applied to three empirical dimensions. Firstly, I assess whether the variety and coordination of labour market and welfare institutions contribute to an enabling opportunity structure for young people. Secondly, I investigate how employability is conceived and delivered to young people. Finally, I assess the outcomes of young people's transitions and their relationship with types of employability measures. I adopt mixed-methods research on the case of the Brussels Capital Region (RBC). I conducted semi-structured interviews with street-level bureaucrats to unveil the cognitive and implementation arrangements of employability delivery. Event history, optimal matching and regression analysis were applied on an original representative longitudinal administrative dataset of young people.