At the start of a project the Requirement Engineer (RE) will define the scope of the project (context diagram), perform stakeholder management and create a common glossary. He also set up rules and checklists for requirements. Next during the elicitation phase, the requirement engineer uses several techniques to gather information: interviews, questionnaires, system documentation, competitor's analysis and brainstorming. The gathered requirements will be documented using natural language and/or models (ERM, Dataflow, UML). It is important to make a distinction between functional and non-functional requirements. After that the requirements will be reviewed (rule set) on completeness, correctness, consistency, unambiguousness, testability, traceability and priority. The RE controls the requirements using configuration management en change management discipline techniques.