ABSTRACT
Observing practices of design professionals makes explicit their reliance upon the construction and transformation of multiple types of artefacts for carrying out their work. This mediating role of things is bound to practices of inquiry as different as those conducted by engineers, scientists, artists and accountants. The emergence of practice is largely related to their use or making of artefacts in different ways. This mediation operating within particular dynamics of their professional engagement unique to their skills, knowledges and the situated contexts within which they are conducted.
