Target State Architecture
A description of the desired future architecture that the organisation is working towards, showing the end-state technology landscape, capabilities, and integration patterns after transformation is complete.
Purpose
The target state architecture provides a north star for transformation programmes, ensuring that individual projects contribute to a coherent future state rather than creating further fragmentation. It guides investment decisions and helps prioritise initiatives.
When to Use
Define during pre-discovery or early discovery when planning a transformation programme. Reference it when making architectural decisions to ensure alignment. Review annually or when strategy changes.
How to Build
Start with the business architecture — what capabilities does the organisation need in the future? What services will it provide? How will users interact with it?
Define the target application landscape: what applications will exist, what will be retired, and how will they integrate? Group by business capability.
Specify the target technology platforms: cloud services, development platforms, integration middleware, data platforms. Define standards for each layer.
Document the target data architecture: where will data live, how will it flow, what are the master data sources?
Show the gap between current state and target state clearly — this gap drives the transformation roadmap.
Tips
- Keep it aspirational but achievable — a target state that is too far from reality will be ignored.
- Show the target state at multiple levels: business, application, data, and technology.
- Include principles and standards that govern the target state.
- Make it visual — architecture diagrams communicate better than text descriptions.
- Review with delivery teams to ensure it is realistic and achievable.
Common Mistakes
- Defining a target state without understanding the current state and the gap.
- Making the target state too detailed, constraining future decisions unnecessarily.
- Not linking the target state to business outcomes, making it a purely technical exercise.
- Ignoring the transition path — a beautiful target state is useless without a way to get there.
- Not reviewing and updating as the organisation's strategy evolves.
Government Context
In UK government, target state architectures should align with the Government Digital Strategy and cross-government reference architectures. They should show adoption of shared platforms (GOV.UK One Login, Notify, Pay), cloud-first hosting, and open standards. CDDO expects departments to have clear target state architectures that demonstrate how legacy IT will be addressed and how services will be modernised.