A document that defines what a proposed system must be capable of doing to solve the problems of a defined set of potential users of such a system. The user requirements specification should be completely independent of any solution-oriented bias and must use terminology from the problem domain of the users. It must be understandable by the intended users who must ‘buy in’ to it. Therefore it is most unlikely to be created using a conventional requirements-analysis method, since these introduce solution bias, representations, and concepts that are rarely understood by (and are irrelevant to) the users.