Experience with Goal-Scenario Coupling in Requirements Engineering

In the context of Requirements Engineering (RE), both goal-driven and scenario-based approaches have proven useful for eliciting, justifying and validating system requirements. In order to overcome some of the deficiencies and limitations of these approaches when used in isolation, proposals have been made to couple goals and scenarios together. The CREWS1-L'Ecritoire approach advocates bi-directional coupling precisely to permit two ways movement between goals and scenarios. The paper reports an experiment using the CREWSL'Ecritoire approach on a large scale business reengineering project conducted for an electricity supply and distribution company. We focussed on a set of issues we found important and of a significance beyond the limits of our brief. We considered three kinds of issue as found in goal-driven approaches, in scenario-based approaches, and those specific to goal-scenario coupling. In this paper, we devote particular attention to the latter and assess the extent to which the goal-scenario coupling helps to resolve the first two.