: Requirements traceability is central to the issue of requirements management, which is essential for producing quality software. Our focus on requirements traceability addresses aspects related to software development and evolution. Our survey deals both with technical and managerial aspects and aims at contextualizing requirements traceability as well as providing basic reference on the subject. Two traceability reference models are used to help the definition of a traceability policy by developers. These models are also reference to the open problems in the area.