I define a requirement as a need that a stakeholder perceives. Also, I call a requirement a capability or property that a system shall have. In addition, I treat a requirement as a documented representation of a need, capability, or property. For example, I can write a user need as a short sentence. Then I can turn it into a system capability. Finally, I can record it in a requirements document.
First, I classify requirements by type. I list business requirements, business rules, constraints, interface requirements, features, functional requirements, non-functional requirements, quality requirements, system requirements, and user requirements. Moreover, I include product requirements, environment requirements, and performance requirements. Specifically, I note that many taxonomies exist. However, none of these lists forms a universal standard. Therefore, I focus on awareness of different requirement types. In other words, I pay attention to coverage. Consequently, I describe the desired change or the planned system completely.
Second, I consider how requirements depend on a solution. For instance, I separate goals from solution details. I label goals as almost solution-independent descriptions of what to achieve. For example, I state a goal like easier and more secure access to cash for all bank customers. Then, I describe system processes. In contrast, I specify system processes as indirect references to the solution. For instance, I give technical specifications for behavior or process flow. Finally, I include solution-specific requirements when a design decision or component structure already exists.
I use short, clear documentation forms. For example, I write requirements in text. Alternatively, I model requirements in diagrams. Moreover, I create formal specifications when needed. Consequently, I increase the potential for automatic processing. Thus, I can analyze diagrams by machine. For instance, I can check state accessibility in state-oriented models. Therefore, I often derive test cases automatically from well-structured requirements.
I maintain traceability actively. First, I define relationships such as refines, realizes, and satisfies. For example, I use <> when a detailed requirement narrows a general one. Then, I apply <> when lower-level requirements produce a higher-level requirement through design. In addition, I use <> to show that my contractor requirements meet client requirements. Consequently, I support verification and evidence that the system meets stakeholder needs.
I plan requirements management at the project start. Thus, I create a Requirements Management Plan. In that plan, I define the process for elicitation, documentation, validation, negotiation, and change. Moreover, I list tools, an information model, attribute schema, prioritization rules, traceability rules, views and reports, versioning, the change process, and variant management. In addition, I assign roles and responsibilities. Specifically, I name the requirements manager who will run the process.
Finally, I emphasize clarity and negotiation. For example, I validate requirements with stakeholders early. Then, I prioritize and version requirements frequently. Moreover, I manage changes with clear rules. Therefore, I reduce risk and improve quality. In short, I treat requirements as needs, system capabilities, and documented artifacts. Consequently, I enable clear communication, traceability, and testable outcomes.