A mate of mine resigned from his CTO role at a mid-market retailer in January. He gave three months’ notice—generous by any standard. When he left at the end of March, his replacement still hadn’t been hired. The company promoted an infrastructure manager into the role with no preparation, no handover documentation beyond what my mate had frantically written in his last two weeks, and no budget for executive coaching.

Three months later, two of the four senior engineers had also left. The new CTO, who was competent technically but had never managed a budget or reported to a board, was overwhelmed. The retailer’s cloud migration program stalled for six months.

This isn’t an unusual story. It’s the default outcome when IT leaders leave organisations that haven’t planned for it.

Why IT Is Worse at This Than Other Functions

Most mature organisations have some form of succession planning for their C-suite. The CFO has a deputy who’s been groomed. The COO has a clear second-in-command. Even the CMO usually has a senior director ready to step up.

But the CTO or CIO role? According to Gartner’s 2025 CIO and Technology Executive Survey, only 23% of organisations have a documented succession plan for their top technology executive. That’s the lowest of any C-suite function.

The reasons are structural. IT leadership sits at the intersection of technical depth, vendor management, strategic planning, and business alignment. It’s hard to find someone internally who covers all four dimensions. Finance can promote a Controller to CFO with reasonable confidence. But promoting a head of infrastructure to CTO is a much bigger leap, because the CTO role increasingly has less to do with infrastructure and more to do with digital strategy, AI readiness, and board-level communication.

The Consequences of Getting It Wrong

When IT leadership transitions fail, the damage compounds quickly. Technical direction drifts because nobody has the authority or context to make architectural decisions. Vendor relationships suffer because the new person doesn’t know the contract history or negotiation pressure points. Strategic initiatives pause because the incoming leader needs to learn the landscape before committing resources.

The team impact is equally severe. Senior engineers and architects who had a trusted relationship with the departing leader start questioning whether the new person understands their work. If the answer is no, they update their LinkedIn profiles.

I’ve seen an organisation lose four of its six principal engineers within eight months of a poorly handled CTO transition. The cost of replacing that institutional knowledge—hiring, onboarding, rebuilding team dynamics—exceeded $2 million. That’s a number that would have justified a serious succession planning investment several times over.

What a Realistic Plan Looks Like

Let me be clear: succession planning doesn’t mean naming a specific replacement years in advance. That’s often impractical in IT, where the skills required for the top role evolve rapidly. What it does mean is building organisational resilience so that a leadership departure creates disruption, not crisis.

Document the undocumented. The biggest risk in any IT leadership transition is the loss of context that lives only in the leader’s head. Vendor negotiation history, architectural decision records, the real reasons behind technology choices (not the sanitised version in the wiki), strategic roadmap rationale, board reporting cadences and expectations. This documentation should be a living process, not a frantic farewell exercise.

Develop two to three potential successors. They don’t need to be ready today. They need to be on a path. Give senior technical leaders exposure to budget management, vendor negotiations, and board presentations. Rotate them through cross-functional projects. The goal is to have people who’ve seen enough of the CTO’s world to not be paralysed by it on day one.

Create a transition playbook. This is a document that outlines the first 90 days for a new IT leader—key stakeholder relationships, in-flight programs, critical vendor contracts and renewal dates, team dynamics and retention risks, budget cycle timing. I’ve built these for several organisations, and the ones that had them survived leadership transitions in half the time of those that didn’t.

Maintain external relationships. Know who the strong CTO candidates are in your market. Retain a recruiting firm on a relationship basis, not just when you need them. Attend ISACA or AISA events where senior IT leaders network. When a departure happens, you want a warm candidate pipeline, not a cold search.

The Board’s Role

This isn’t just the CTO’s responsibility. Boards and CEOs need to ask the question directly: what happens if our technology leader leaves tomorrow? If the answer involves a lot of hand-waving and “we’d figure it out,” that’s a governance gap.

The investment required is modest. A few hundred hours per year of deliberate development for potential successors, a living documentation practice, and an annual review of the succession plan. Compare that against the cost of a botched transition—stalled projects, lost engineers, vendor negotiating power evaporating, strategic momentum dying—and it’s one of the highest-return governance investments an organisation can make.

Yet almost nobody does it. And every year, the same preventable disaster plays out at hundreds of Australian companies. We keep learning this lesson the hard way.