Phase H: Architecture Change Management — Keeping Architecture Alive After Go-Live

Phase: Phase H — Architecture Change Management Perspective: Enterprise Architect

Architecture is not a project deliverable — it is a living capability. Phase H ensures that as the world changes, your architecture responds deliberately rather than eroding silently.

Key Inputs

Implemented architecture and lessons learned
Technology change triggers (new platforms, vendors)
Business change triggers (M&A, regulation, strategy shifts)
Architecture performance metrics
Stakeholder feedback
Industry trend analysis

The Process

Monitor architecture performance against KPIs
Assess change triggers for architecture impact
Conduct periodic architecture health reviews
Manage architecture change requests
Determine if changes require a new ADM cycle
Update architecture repository and baselines

Deliverables

Architecture Change Requests
Updated Architecture Baselines
Architecture Performance Report
Lessons Learned Register
Change Impact Assessments
Updated Roadmap (if required)

Practitioner Perspective

Phase H is where most organisations fail at enterprise architecture. They complete a cycle, implement something, and let the architecture become stale. Within 18 months, the documented architecture no longer reflects reality, and the EA function loses credibility with both business and IT.

Establish a cadenced Architecture Review — quarterly at minimum. Use it to assess the health of the current architecture against the original target and against emerging requirements. Make it a standing governance event, not an ad-hoc exercise triggered by crisis.

Classify incoming changes using a three-tier model:

Tactical changes: no ADM cycle needed — update the repository and record the decision
Significant changes: partial re-entry to ADM — re-run the affected phases
Transformational changes: full new ADM cycle — treat as a new architecture engagement

Build relationships with your technology intelligence sources — vendor roadmaps, analyst briefings, internal innovation teams, regulatory horizon-scanning — so architecture changes lead strategy rather than lag it.

The most common mistake: Treating Phase H as optional. It is the phase that preserves the value of all previous phases. Without it, architecture has a shelf life of approximately two years before it becomes misleading rather than useful.

Practical tips:

Establish architecture KPIs at Phase A and measure them from go-live: time to onboard a new application, number of integration exceptions, cost per business capability — make architecture value quantifiable
Create an "architecture drift register": when you identify that reality has diverged from documentation, log it and set a resolution date
Run an annual Architecture Health Check as a formal event — it maintains executive attention and gives the EA function a regular opportunity to demonstrate value
Build a Technology Radar for your organisation, updated quarterly, tracking emerging, adopted, and sunset technologies

Part of a series: TOGAF from an Enterprise Architect's Perspective