In this article we examine the difficulties of knowledge communication among experts and decision makers. We begin by outlining where and how the communication of expertise from specialists to managers is crucial. We then review theoretical constructs that highlight knowledge transfer problems among experts and decision makers. On the basis of this review and using the results from six focus groups and thirty interviews with engineers and managers, we categorise these transfer challenges into five major groups. We distinguish among expert‑ and manager‑caused problems, reciprocal problems, problems due to the interaction situation and problems caused by the organisational context. These categories can be used to guide research on the micro‑aspects of knowledge transfer. Managers can use these problem categories to identify and reduce knowledge transfer barriers in their interaction with specialists.