An important aspect in SoS is the realization of the concerns in different systems that work together. Identifying and locating these concerns is important to orchestrate the overall activities and hereby to achieve the overall goal of the SoS. Moreover, concerns in SoS are rarely stable and need to evolve in different ways and different times in accordance with the changing requirements. To manage the SoS and cope with the evolution of concerns it is necessary that the dependency links between the concerns and the system elements can be easily traced. In this paper, we present the different traceability requirements and the corresponding metamodel to support modeling traceability and supporting traceability analysis approaches within the SoS context.