Service Transition Transformation for a UK Defence Organisation

Sunfish was engaged by a UK defence organisation whose IT function had evolved into a separate operating model from the wider business. The result was a fragmented, inconsistent environment with a low service transition maturity. Sunfish was brought in not to deliver a single project, but to lead a service management transformation: defining what good looked like and building a complete, end-to-end service transition capability the organisation's own teams could adopt and sustain.

The client's IT function had drifted into its own operating model, separate from the rest of the organisation. That lack of cohesion produced a low-maturity service transition capability, with unclear accountability, poor alignment between project delivery and service operations, and services being deployed without sufficient documentation or support readiness.

Operationally, this created a snowball effect. Unresolved upstream issues flowed into live environments, leading to missed SLAs, increased incident complexity and growing reputational risk. Cultural resistance to change, siloed working and resource constraints compounded the problem further, driving significant financial inefficiency and unnecessary project costs.

Sunfish approached the engagement as a service management transformation rather than a traditional delivery project. Acting as a credible service leadership voice, we defined what good looked like and designed a complete, end-to-end service transition process. This included establishing clear accountability through RACI frameworks, applying lean principles to remove inefficiency, and identifying broader systemic gaps such as the absence of service design and misaligned project methodologies. A key insight was the need for a holistic model aligning service design, service transition and project delivery, alongside stronger supplier ecosystem alignment.

Implementation followed an agile service management approach, combining ITIL v3 process rigour with ITIL v4's focus on value. Through iterative workshops, continuous feedback and a "start where you are" mindset, the solution was refined in collaboration with the client. Transformation was treated as an ongoing evolution, validated through both early improvements and measurable outcomes.

Sunfish established a structured, end-to-end service transition framework with clear governance, defined roles and streamlined processes. This shifted the organisation from a chaotic, siloed state to a more controlled, collaborative and efficient operating model, designed for both speed and quality.

"Before Sunfish engaged with us, our IT function was operating in a state of fragmentation, siloed teams, unclear accountability and services being deployed without the readiness or documentation to support them. The downstream impact was real: missed SLAs, rising incident complexity and the kind of reputational and financial risk that compounds quickly when left unaddressed.

What Sunfish brought was not just a process fix, but a genuine transformation in how we think about service delivery. They didn't arrive with a pre-packaged solution, they took the time to understand where we actually were, defined what good looked like for our environment, and built an end-to-end service transition framework that gave us structure, clear ownership and a way of working that our teams could actually adopt.

The results have been tangible. We've moved from a CMMI Level 1 maturity baseline and are tracking toward Level 3. Operationally, we're seeing stronger collaboration across functions and a measurable reduction in risk. The financial case is equally compelling, mature service transition is expected to deliver cost reductions in the range of 20–30%, with fewer project overruns and significantly lower remediation costs.

Sunfish operated as a trusted partner throughout, credible at the leadership level, practical at the delivery level, and genuinely invested in our success. If your IT function is carrying the weight of unresolved structural issues, they are the team to bring in."