Tracing Back from Requirements

The problem of achieving traceability from a design, and its associated documentation, back to a requirements specification has been the subject of a considerable amount of discussion. A much less frequently discussed and, I shall argue, much more interesting problem, is that of tracing back from the requirements specification into the domain which gave rise to those requirements. The tendency, in practice, is to stop conventional traceability with the procurer’s signature on the requirements specification. In some senses this avoids the really hard problem. Tracing between successive representations with a defined relation to each other- specification & design, design & implementation, specification & test plan- is much easier than tracing back from the requirements specification to the tangled collection of overlapping and potentially inconsistent perspectives and statements which are the stuff of requirements elicitation. Change, consequent upon system evolution, will commonly require a better understanding of the requirements which can only be achieved b