Formulating Engineering Systems Requirements

Requirements are essential to coordinate purpose-driven activities distributed over several stakeholders. Requirements control the complex dynamics of socio-technical systems consisting of stakeholders and engineering artefacts and are, therefore, crucial for the success of socio-technical projects. Requirements management is challenging, in particular for complex engineering systems. This chapter discusses challenges (1) from a requirement receiver’s perspective, focusing the indeterminacy of expectations; (2) from a requirement providers perspective, focusing on technical complexity; and (3) general challenges from an overall perspective. The chapter provides an overview of approaches to manage and treat requirements and links them to the core activities of requirements management: elicitation, analysis, triage, specification, as well as verification and validation. Typical forms of documentation and formulation rules are presented. Finally, we discuss the importance of quantitative analysis methods. Approaches based on simulation, isoperformance analysis, analytical target cascading, and solution space optimisation are briefly summarised.