Traceability matrix

A requirements traceability matrix (RTM) is a table that links requirements to their origin and traces them through the project life cycle, from business need to design, development, testing and delivery. It ensures that each requirement is delivered and tested, and helps manage changes. It is an output of the Collect Requirements process in PMBOK.

Contents (typical columns)

Other attributes: priority, owner, version, acceptance criteria, and change request link.

Types of traceability

• Forward: from requirements to design, code and tests (are all requirements implemented and tested?).
• Backward: from deliverables back to requirements (is anything built that was not required? avoids gold plating).
• Bidirectional: both.

Business need -> Requirement -> Design
     -> Code -> Test case -> Acceptance

Uses and importance

1. Ensures all requirements are implemented and nothing is omitted.
2. Gives evidence for scope validation and customer acceptance.
3. Supports scope control: shows impact of a change request on design, code and tests.
4. Helps in estimating the effort of changes.
5. Supports testing coverage analysis.
6. Provides accountability and communication between business and technical staff.
7. Useful for audits and compliance.

Maintenance

Update when requirements change, with version control, and review at phase ends.

Example: When a client requests changing report format (R-02), the RTM shows affected design, code module and test cases, so the manager can estimate the effort accurately.