Legacy System Modernisation RACI Matrix
This is a practical guide to building a raci matrix for a legacy system modernisation project — a grid mapping tasks to who is Responsible, Accountable, Consulted and Informed, adapted to the realities of modernising or replacing ageing core systems.
What a RACI Matrix is
A raci matrix is a grid mapping tasks to who is Responsible, Accountable, Consulted and Informed. For the full concept and how it works in general, see RACI Matrix. On a legacy system modernisation project it plays the same role, tuned to this kind of work.
Why it matters for a Legacy System Modernisation project
Legacy System Modernisation projects live or die on modernising or replacing ageing core systems. A well-built raci matrix gives the team a shared, explicit reference for exactly that — reducing ambiguity, aligning stakeholders, and making problems visible early enough to act. Skipping it, or doing it generically, is how legacy system modernisation projects drift into avoidable delay and cost.
What to include
- Activities as rows
- Roles as columns
- One Accountable per row
- Responsible / Consulted / Informed
Legacy System Modernisation-specific considerations
Tailor the raci matrix to the risks that most often derail legacy system modernisation projects:
- Undocumented legacy behaviour
- Phased cutover risk
- Knowledge loss
Example
On a real legacy system modernisation project, the raci matrix would be shaped by modernising or replacing ageing core systems. In particular, it should explicitly account for the project’s biggest risks — undocumented legacy behaviour, phased cutover risk, knowledge loss — rather than treating them as afterthoughts.