A Representational Framework for Scenarios of System Use

Scenarios are becoming widely used in three areas of system development: software engineering, human–computer interaction (HCI), and organisational process design. There are many reasons to use scenarios during system design. The one usually advanced in support of the practice is to aid the processes of validating the developers’ understanding of the customers’ or users’ work practices, organisational goals and structures, and system requirements. All three areas identified above deal with these processes, and not surprisingly this has given rise to a profusion of scenario-based practices and representations. Yet there has been little analysis of why scenarios should be useful, let alone whether they are. Only by having such a framework for understanding what scenarios are, and what they are for, can we begin to evaluate different scenario approaches in specific development contexts. This paper is a contribution toward such a framework. We lay out a space of representational possibilities for scenarios and enumerate a set of values or criteria that are important for different uses of scenarios. We then summarise several salient representations drawn from the software engineering, HCI, and organisational process design communities to clarify how these representational choices contribute to or detract from the goals of the respective practices. Finally, we discuss how scenario representations from one area of design may be useful in others, and we discuss the relationship between these representations and other significant early-design and requirements engineering practices.