Requirements management is the process of documenting, analyzing, tracing, prioritizing and agreeing on requirements and then controlling change and communicating to relevant stakeholders. It is a continuous process throughout a project. A requirement is a capability to which a project outcome (product or service) should conform.
The purpose of requirements management is to ensure that an organization documents, verifies, and meets the needs and expectations of its customers and internal or external stakeholders. Requirements management begins with the analysis and elicitation of the objectives and constraints of the organization. Requirements management further includes supporting planning for requirements, integrating requirements and the organization for working with them (attributes for requirements), as well as relationships with other information delivering against requirements, and changes for these.
The traceability thus established is used in managing requirements to report back fulfilment of company and stakeholder interests in terms of compliance, completeness, coverage, and consistency. Traceabilities also support change management as part of requirements management in understanding the impacts of changes through requirements or other related elements (e.g., functional impacts through relations to functional architecture), and facilitating introducing these changes.
Requirements management involves communication between the project team members and stakeholders, and adjustment to requirements changes throughout the course of the project. To prevent one class of requirements from overriding another, constant communication among members of the development team is critical. For example, in software development for internal applications, the business has such strong needs that it may ignore user requirements, or believe that in creating use cases, the user requirements are being taken care of.
Requirements traceability is concerned with documenting the life of a requirement. It should be possible to trace back to the origin of each requirement and every change made to the requirement should therefore be documented in order to achieve traceability. Even the use of the requirement after the implemented features have been deployed and used should be traceable.
Requirements come from different sources, like the business person ordering the product, the marketing manager and the actual user. These people all have different requirements for the product. Using requirements traceability, an implemented feature can be traced back to the person or group that wanted it during the requirements elicitation. This can, for example, be used during the development process to prioritize the requirement, determining how valuable the requirement is to a specific user. It can also be used after the deployment when user studies show that a feature is not used, to see why it was required in the first place.