Sandwich placements and other integrated work and study schemes are increasingly advocated as a key means by which universities can promote students' employability. However, there is little understanding of how successful placements work in terms of facilitating learning and development. Drawing on three longitudinal case studies of students who have undertaken placements, two successfully, we use Bourdieu's conceptions of habitus and field to theorise successful placements. We establish the importance of the initial "fit" between an individual's habitus and the field they enter to undertake a sandwich placement, together with the extent of the "horizon for learning" emerging through the continuing interaction of habitus and field. Further, we argue that this relational approach can help us to recognise the importance of non-cognitive aspects of informal learning through placements and to understand how successful placements can be the catalyst for better grades on return to university study.