Cost estimation of changes to software systems is often inaccurate and implementation of changes is time consuming, cost intensive, and error prone. One reason for these problems is that relationships between documentation entities (e.g., between different requirements) are not documented at all or only incompletely. In this paper, we describe a constructive approach to support later changes to software systems. Our approach consists of a traceability technique and a supporting tool environment. The tracing approach describes which traces should be established in which way. The proposed tool environment supports the application of the guidelines in a concrete development context. The tool environment integrates two existing tools: a requirements management tool (i.e., RequisitePro) and a CASE tool (i.e., Rhapsody). Our approach allows traces to be established, analyzed, and maintained effectively and efficiently.