Despite numerous problems with outcome-based assessment systems, claims that they enhance learners' motivation and autonomy resonate with research interest in how young people develop cultural and social capital. However, research has not yet explored the ways in which assessment systems affect the forms of capital embedded within them. This paper applies concepts from a growing body of work on social and cultural capital in education to data from a study of assessment policy and practice in the Advanced General National Vocational Qualification (GNVQ) in two further education colleges. It evaluates how norms, practices and dynamics created by the GNVQ assessment regime interacted with other factors in students' lives and the learning programme itself. These interactions shaped cultural and social capital inside a learning 'comfort zone' and affected students' motivation and attitudes to learning. The article evaluates the implications of these factors for the types of cultural and social capital that may be on offer in different assessment regimes. In particular, it raises questions about the extent to which social and cultural capital are empowering or constraining, and offers ideas for further research in this area.