The paper reports on a mixed methods study that sought to analyse determinants of youth labour market and educational disengagement in Peru. It begins by questioning the widespread focus on NEET–youth not in employment, education or training–as a measure of youth vulnerability in countries with extensive informal labour markets where labour precarity can be as problematic as unemployment for young people’s futures. A broader category of ‘urban vulnerable’ youth, including both NEET and precarious workers, is proposed and used as the basis for analysing the factors that influence young people’s trajectories. Key factors and shocks in youth trajectories are identified through qualitative life histories, and are tested using cross-section and panel survey data. Findings from the study have implications for the analysis of youth labour market vulnerability in the Global South, as well as for the policies that seek to address this problem.