To modify complex computer-based systems requires a detailed understanding of their functionality. Requirements Traceability can help the engineer to gain that understanding, but several surveys have observed that traceability information is poorly recorded. We argue that the cause is the lack of direct perceived benefit to the main development process. As a consequence traceability information will be incomplete, inaccurate and out-of-date. We propose a method of recording traceability information, a Traceable Development Contract (TDC), as a means of reducing this problem by tackling the issue of an upstream functional development team imposing changes on a downstream development team. The contract makes the recording of traceability information beneficial to both development teams.