Strategic Outline Business Case Playbook
Guide Origin: Official | ArcKit Version: [VERSION]
/arckit:sobc creates a Strategic Outline Business Case (SOBC) using the UK Government Green Book 5-case model.
Inputs
| Artefact |
Purpose |
Requirements (ARC-<id>-REQ-v1.0.md) |
What the project must deliver |
| Stakeholder drivers |
Business context and strategic alignment |
| Risk register |
Key risks and assumptions |
| Architecture principles |
Technology constraints and standards |
Command
Output: projects/<id>/ARC-<id>-SOBC-v1.0.md
Auto-versioning: Re-running this command when a document already exists automatically increments the version (minor for refreshed content, major for changed scope) instead of overwriting.
SOBC Structure (5-Case Model)
| Case |
Contents |
| Strategic Case |
Why is change needed? Strategic fit, policy alignment, objectives |
| Economic Case |
What delivers best value? Options analysis, cost-benefit, VfM |
| Commercial Case |
How will it be procured? Procurement strategy, market engagement |
| Financial Case |
Is it affordable? Funding, budget, financial implications |
| Management Case |
How will it be delivered? Governance, timeline, assurance |
Strategic Case Components
| Component |
Contents |
| Strategic Context |
Policy drivers, strategic priorities |
| Case for Change |
Current situation, problems, why change is needed |
| Investment Objectives |
SMART objectives for the investment |
| Existing Arrangements |
Current state and its limitations |
| Business Needs |
What the organization requires |
| Scope |
What's included/excluded |
| Benefits |
Expected benefits and how measured |
| Risks |
Key strategic risks |
| Constraints |
Boundaries and limitations |
| Dependencies |
Related projects and external factors |
Economic Case - Options
| Option Type |
Description |
| Do Nothing |
Continue as-is (baseline) |
| Do Minimum |
Minimal intervention |
| Do Something (Options 1-3) |
Alternative approaches |
| Preferred Option |
Recommended approach with rationale |
Business Case Lifecycle
| Stage |
Document |
Purpose |
| Pre-SOC |
Strategic Assessment |
Initial exploration |
| SOC |
Strategic Outline Case |
Strategic direction |
| SOBC |
Strategic Outline Business Case |
Preferred way forward |
| OBC |
Outline Business Case |
Detailed analysis |
| FBC |
Full Business Case |
Investment decision |
One-Page Workflow
| Phase |
Key Activities |
ArcKit Commands |
| Discovery |
Define requirements and stakeholders |
/arckit:requirements, /arckit:stakeholders |
| Risk |
Identify and assess risks |
/arckit:risk |
| Business Case |
Create SOBC |
/arckit:sobc |
| Architecture |
High-level design |
/arckit:diagram, /arckit:hld-review |
| Procurement |
Market engagement |
/arckit:sow, /arckit:gcloud-search |
Review Checklist
- Strategic fit with government and departmental priorities clear.
- Case for change compelling with evidence.
- Investment objectives are SMART.
- At least 4 options considered (including do nothing).
- Preferred option has clear rationale.
- Benefits identified with measurement approach.
- Key risks and mitigations documented.
- Procurement route identified.
- Funding requirements clear.
- Governance and delivery approach outlined.
Treasury Approval Thresholds
| Threshold |
Approval Required |
| <£5m |
Departmental |
| £5m-£25m |
Department + CDDO |
| >£25m |
HMT + IPA |
Note: Thresholds vary by department and project type
Key Principles
- Evidence-Based: All claims supported by data and analysis.
- Options Appraisal: Genuinely consider alternatives.
- Benefits Focus: Clear, measurable benefits with owners.
- Risk Awareness: Honest about risks and uncertainties.
- Proportionate: Detail appropriate to investment size.
wehub-resource-sync