This thesis investigates context specific properties of codebooks, which is a concept introduced by Cowan, David and Foray, in their paper published in Industrial and Corporate Change, June 2000. The conditions for transfer of knowledge using codebooks between professional communities are explored. To do this, a case study from the Norwegian Offshore Industry is used. Open-ended interviews have been carried out in Aker Engineering and Aker Stord. Both companies belong to Aker Maritime’s business area, Aker Oil and Gas, which is a major actor in large development projects on the Norwegian Continental Shelf. Recent contributions inside the field of knowledge economy and knowledge management have called attention to the complex cognitive elements of perceiving knowledge. Hence, possibilities of interpretation and utilization of knowledge embedded in a codebook are dependent on the temporal, spatial, social and cultural context, in which knowledge is created, communicated and de-codified. The case does primarily consider the steel process in offshore development projects. That is, the transfer of technological knowledge from the structural engineering disciplines, to pre-fabrication and assembly of the structure at the yard, not including special equipment and piping. Codebooks used in this transfer are mainly the package of steel drawings and a 3D-computer model of the structure. Transfer of technological knowledge from the engineering phases to the fabrication phases in a development project is a case of knowledge transfer between two professional communities. Engineers responsible for design (the design community) have very different priorities, professional norms and perceptions of “appropriate” knowledge than the operators responsible for the actual production of the offshore structure (the production community). As a result, the design community and the production community associate different knowledge with the codebooks.The thesis investigates how an intersection of cognitive contexts between the two communities is necessary to secure efficient transfer of knowledge through engineering drawings. A total overlap in contexts is however not desirable, as this necessitates similar competences and background knowledge. Different skills are needed for the two communities to attend to their dissimilar responsibilities in the execution of a project.Stabilization and, to some degree, standardization of language (the symbolic representation in the drawings) and the knowledge itself (the technical solutions) are seen as imperative for unambiguous interpretation of knowledge embedded in the codebook.Due to insufficiency in intersection of cognitive contexts, resulting from limits in the stabilization and standardization of language and technical solution, mistakes, shortcomings and interpretation problems are frequently experienced on the drawings. Since the two communities are located far apart geographically direct personal interaction between the communities is largely restricted. Hence, mediators become important in the transfer of the codebook.Two categories mediators are identified. Mediators I hold intermediate functions in a project. They provide additional flexibility to the rather rigid knowledge, embedded and manifested in written documents. Moreover they function as interpreters and co-ordinators of knowledge. Mediators II have primarily long-term functions as mediators, and contribute to enhance and develop the intersection of cognitive contexts, and have caused what the respondents called ‘reduction in cultural differences’ between the communities.