Description: Evidence suggests a deficit in the definition and understanding of 'knowledge' in Work-based Learning (WBL) programmes. Rather, the emphasis is almost entirely on 'learning'- with the term 'knowledge' used in unclear ways. In some of the literature, we see assumptions that there are no differences between various forms of knowledge (e.g. between subject knowledge and workplace knowledge). In other literature, the implication is that there are similarities and continuities between forms of knowledge that are different but permeable. Other perspectives place greater emphasis on knowledge difference, either by (counter-) privileging WBL over formal, subject-based learning or by seeking to develop more knowledge-informed curricular and pedagogic approaches to enhance the validity and success of WBL programmes. This paper adopts the last position (a 'hard boundary' approach) and holds that without a thorough understanding of different knowledge structures, it is difficult to develop curricula and pedagogy in WBL programmes. Such a state of affairs promotes a situation where terms like 'integration' and 'transfer' are used indiscriminately and in loose and over-optimistic ways. The hypothesis is that this leads to sometimes disappointing outcomes for stakeholders in the WBL enterprise (providers, learners and employers) and reduces the economic and social benefits of WBL programmes. The paper argues that critical realism and the work of curriculum theorist Basil Bernstein (and those who have used and developed his theories) provides a generative framework and set of concepts firstly, to establish what knowledge structures characterise the various components of WBL programmes, and secondly, to identify, describe, analyse and envisage curricular and pedagogic logics and possibilities for the most efficacious linkages between them. His work has, to date, been under-used in the theory and practice of WBL. Methodology: In the light of the above, a Bernsteinian theoretical and conceptual framework is established for use in an empirical research project on WBL (in the context of intermediate-level qualifications), located at the Institute of Education, University of London, and funded by the London The London Chamber of Commerce and Industry Commercial Education Trust. The development of such a framework began in the writer's PhD and continued through collaboration with other theorists working with Bernstein's resources and through attendance at the Fourth International Basil Bernstein Symposium in July 2006. Conclusions: The framework locates WBL in a critique of the widely pervasive educational philosophies of experientialism, constructivism and 'progressivism'. In so doing, anticipatory analysis suggests that opportunities are presented for new theorisations and conceptualisations of WBL curricula and pedagogy. Based on a 'hard boundary' approach to knowledge, these may appear to be less 'progressive' than other approaches, but the paper will argue that the reverse is more likely to be the case.