This article examines how different forms of vocational knowledge are constructed from social sources. Using a Vygotskian framework it is claimed that in different ways vocational knowledge is shaped by history, community and ontogeny through microgenetic development. This process of ongoing problem-solving links social circumstances to the development of the cognitive structures necessary to conduct vocational practice. It is held that such findings help explain the limitations of transfer and also the need to conceptualise expertise at the particular community of practice, rather than at some disembedded level of practice.