Requirements management involves a team effort to establish and maintain agreement between the stakeholders and the development team on what the system should do.
In a typical project, several types of requirements should be considered , including high-level features, as well as more detailed functional and nonfunctional requirements and use cases.
Maintaining requirement attributes and traceability are keys to managing the scope of the project effectively and handling changing requirements throughout the project lifecycle.
User-interface design focuses on the key needs and goals of the users in the visual shaping of the user interface in order to build a user -centered system and meet usability requirements.
Rational tools support the capture, visual modeling, and management of requirements, their attributes, and traceability.