Abstract : We consider requirements change due to system evolution which results from contextual forces such as the decision to standardise practices across subsidiaries of a company. Our experience with the financial branch of the French Renault group is that eliciting change requirements poses its own specific problems. We propose to model change as a set of gaps between the requirements specification of the current and the future system. Our approach is to define a generic typology of gaps to facilitate a precise definition of change requirements. It adopts a goal oriented requirements specification and shows how to customise the generic gap typology to this specific requirements representation formalism. The paper presents the approach to elicit gaps and illustrates it with the Renault case study.
