In identifying this separate and distinctive kind of linguistic expertise, the idea of interactional expertise makes a clear break with other theories of expertise, particularly those developed in Science and Technology Studies, which tend to see expertise as a social status granted by others rather than a property of the individual. As discussed in more detail below, the idea of interactional expertise also differs from more traditional phenomenological theories of expertise, in which the expertise of the contributory expert is well-recognised but the distinctively linguistic expertise of the interactional expert appears to have been overlooked. In this context, it must be emphasised that interactional expertise is a tacit knowledge-laden ability and thus similar in kind to the more embodied contributory expertise. This means that, like contributory expertise, interactional expertise cannot be acquired from books alone and it cannot be encoded in computerised expert systems. It is a specialised natural language and, as such; it can only be acquired by linguistic interaction with experts. The difference between interactional and contributory expertise is that, in the case of interactional expertise, the tacit knowledge pertains to the language of the domain but not its practice. In the case of contributory expertise, tacit knowledge relating to both the language and practice must be acquired.