The use and value of scenario planning for systems engineering

Projects are often approached with the assumption that requirements are known and stable before system design can begin. Systems can be designed for multiple anticipated operating conditions by using use cases and scenarios, which explore di erent ways in which users may seek to interact with the system under development depending on their needs and the circumstances. It is generally assumed, however, that the operating environment and the corresponding set of scenarios is static - that it doesn't change over time. This may work reasonably well for short-lived systems, and systems that are designed to be relatively independent in their behaviour (such as buildings, bridges and power stations), but for systems that contribute to systems of systems such as military aircraft, a more exible view of the future operating scenarios is needed. Furthermore, long-life systems and systems with long development times also need to creatively anticipate the future business environment. Only by doing this can the system continue to add value to its supersystem (or the enterprise for whose bene t it was designed). This paper evaluates scenario planning as an approach for managing the uncertainty of the future business environment. The history of scenario planning is explored, as well as its use and value in a range of industry sectors including defence, space and energy (oil and gas). The role of scenario planning in the development of new technology is discussed, nding that scenario planning could usefully be added to the systems design toolkit.