The departure of a senior technology leader creates risks that no succession plan fully addresses. This is not because organisations fail to plan — most of them do, in the formal sense of identifying successor candidates and maintaining role profiles. It is because the knowledge that matters most in a technology leadership transition is almost never the knowledge that succession plans capture.
The knowledge in the succession plan is explicit: the skills, the experience, the track record of delivery. The knowledge that determines whether the technology function continues to perform well after the transition is implicit: the undocumented decisions, the institutional context, the relationships, the working agreements that exist in no document but hold the architecture together. That knowledge is not transferable through a succession plan. It requires deliberate effort to surface, capture and transmit — effort that organisations consistently fail to invest in because the departure of a senior leader always feels unexpected, even when it should not.
The Institutional Knowledge Problem
Senior technology leaders accumulate knowledge of two kinds. The first kind — knowledge of the technology estate, the architecture, the programmes in flight, the supplier relationships — is, in principle, documentable. In practice, it is frequently not documented, because the leader in question has been too busy running the function to document what they know, and because organisations do not create the structural incentives for documentation that would change this.
The second kind of knowledge is harder. It includes: the context behind decisions that look arbitrary but are not — why the integration was built that way, what constraint was being worked around, what political agreement was reflected in that architectural choice. It includes the relationships with key individuals — suppliers, regulators, board members — where the working relationship has significant personal dimension and cannot simply be reassigned. It includes the judgements about the technology estate that exist only in the leader's head: which systems are more fragile than they appear, which programmes have risks that are not captured in the status report, which supplier relationships are under stress that is not yet visible.
When the CTO leaves, all of this knowledge leaves with them. What remains is a function that has the documented process and the formal architecture, but has lost the institutional memory that made the documented process work in practice.
"The technology function does not fail immediately when a strong CTO leaves. It fails slowly, over the eighteen months that follow, as undocumented knowledge proves critical in situations where it is no longer available."
What Organisations Get Wrong About Technology Leadership Transitions
They treat succession as a selection problem rather than a knowledge transfer problem. Most of the energy in technology leadership transitions goes into finding the right successor — assessing candidates, managing the search, negotiating terms. Very little energy goes into the knowledge transfer that will determine whether the successor is set up to succeed. A highly capable new CTO who does not understand the undocumented context of the decisions they are inheriting will spend months — sometimes more than a year — rediscovering things their predecessor knew, making decisions that conflict with the institutional logic they are unaware of, and rebuilding relationships that should not have needed rebuilding.
They compress the transition period under commercial pressure. The natural instinct when a senior leader announces their departure is to move quickly — to name a successor, manage internal anxiety, and demonstrate organisational continuity. The transition period, where the departing leader and their successor work in parallel, is consistently compressed under this pressure. In most cases, the transition period that would allow adequate knowledge transfer is significantly longer than what actually happens.
They do not ask the right questions. The handover process typically focuses on current programmes, current budgets, and current organisational issues — the explicit, documented content of the role. It rarely systematically asks the departing leader for the implicit knowledge: the undocumented decisions and their context, the relationships that need special handling, the risks that are not visible in the formal reporting, the things they would want their successor to know that are not written anywhere. Asking those questions requires deliberate structure — a guided knowledge transfer process rather than an informal handover.
In regulated financial institutions, senior technology leadership transitions have a regulatory dimension that adds complexity to an already difficult process. BaFin's fit-and-proper requirements for key function holders, the notification obligations under DORA for changes to the ICT governance structure, and the continuity requirements under operational resilience frameworks all impose constraints on how a technology leadership transition can be managed. Institutions that plan their transitions without accounting for these regulatory obligations — particularly the fit-and-proper assessment timeline, which can be longer than the commercial transition timeline — create regulatory risks that are unnecessary and avoidable.
What Should Happen Instead
The organisations that manage technology leadership transitions well do several things differently from those that do not.
They treat technology leadership knowledge as an institutional asset and manage it accordingly. This means creating the conditions for ongoing knowledge documentation — not as a succession-planning exercise but as a regular operational practice. Architecture decision records, programme status narratives, relationship maps, and documented risk assessments that reflect the leader's actual view of the estate — not just what the formal reporting says — are valuable whether or not a transition is imminent.
They build structured knowledge transfer into the transition process. A guided knowledge transfer process — with explicit questions about undocumented decisions, implicit risks, relationship context and the things the departing leader would want their successor to know — consistently produces better outcomes than an informal handover. This process should be facilitated by someone who knows what questions to ask, can hold both the departing and arriving leader in productive conversation, and can capture what emerges in a form the successor can actually use.
They protect the transition period from commercial compression. The pressure to manage the transition quickly — to avoid uncertainty, to retain team confidence, to satisfy board anxiety — needs to be balanced against the cost of an inadequate knowledge transfer. In my experience, the minimum adequate transition period for a complex technology leadership role is three to four months of genuine overlap. Most organisations allow less than half of that.
They explicitly manage the relationship dimension. The departing leader should make deliberate introductions — not just transfers of the contact — to the relationships that matter most. The new leader's first months should include structured engagement with the key relationships, supported by briefings from the departing leader that provide context the new leader cannot acquire from documentation alone.
- Does your organisation maintain documentation of architectural decisions and their context — not just what was decided, but why, and what alternatives were considered?
- If your technology leader left tomorrow, could their successor find a documented map of the relationships, undocumented risks, and implicit knowledge that determines how the function actually works?
- Is the planned transition period adequate for genuine knowledge transfer — three months or more of real overlap — or has it been compressed to satisfy organisational anxiety about continuity?
- Have you accounted for the regulatory obligations that a technology leadership transition triggers in your jurisdiction?
- Is the knowledge transfer process structured — with explicit questions and facilitated capture — or is it informal and dependent on the departing leader's willingness to surface what they know?
Technology leadership transitions will always carry risk. The knowledge accumulated over years in a complex role cannot be fully transferred in any transition period. What can be managed is the gap — the distance between what the departing leader knows and what the arriving leader needs to know to be effective. Closing that gap requires time, structure and deliberate effort. It is consistently worth the investment.