In our first blog, we cut through the clean core confusion with straight answers to the questions customers actually ask. In our second, we exposed the uncomfortable truth: most clean core initiatives quietly fail despite good intentions and detailed PowerPoints.
Now comes the hard part: making it work in the real world.
This isn’t another theoretical framework. It’s a practical blueprint based on what actually works , distilled from organizations that moved beyond clean core aspirations to sustainable clean core discipline.
The Reality Check: Why “Just following the guidelines” Isn’t enough
Before we dive into solutions, let’s address the elephant in the room: SAP’s clean core documentation tells you what to do, not how to make it stick when your CFO is breathing down your neck about project timelines.
The companies that succeed don’t just implement clean core, they build organizational systems that make dirty core impossible. They create environments where choosing the clean path becomes the natural, easy choice.
Here’s how they do it.
Foundation 1: create Clean Core clarity that survives contact with reality
The problem: Most teams operate with different definitions of “clean.” Your architect says BTP extensions are clean. Your developer thinks any API call is clean. Your business user doesn’t care as long as it works.
What works: Document your clean core boundaries with surgical precision, then test them against real scenarios.
Your Clean Core charter should define:
- Green zone: What's always acceptable (standard SAP, approved BTP patterns, key user extensibility)
- Yellow zone: What requires architectural review (complex integrations, performance-critical extensions)
- Red zone: What's never acceptable (direct table modifications, core program changes, undocumented user exits)
But here’s the crucial part: Include decision trees for common scenarios:
“If the business needs a custom approval workflow, the clean approach is X. If they need custom pricing logic, the clean approach is Y. If they need real-time data synchronization, the clean approach is Z.”
Real example: A Dutch manufacturing client created a one-page “Clean Core Decision Tree” that developers could use in 30 seconds. Result: 85% fewer architectural escalations and 40% faster development cycles.
Foundation 2: Build governance that works when nobody’s watching
The Problem: Most governance is reactive. Someone builds something dirty, governance finds it later, and by then it’s too late to change without breaking deadlines.
What Works: Shift-left governance that prevents problems instead of just catching them.
Proactive governance architecture:
- Intake gate: Every development request goes through a 15-minute clean core assessment before approval. Quick pattern match against your charter
- Design gate: Architectural review happens at 25% design completion, not at go-live. Early enough to change direction without destroying timelines.
- Code gate: Automated scanning with tools like ATC (ABAP Test Cockpit) that flag potential violations before they reach production.
- Exception process: Clear escalation path for genuine business exceptions, with sunset dates and mandatory cleanup schedules.
The secret weapon: Make governance additive, not subtractive. Instead of just saying “no,” governance should provide clean alternatives.
Real example: A financial services client embedded clean core questions directly into their project request system. Simple checkboxes that force teams to think clean from day one. Result: 90% of projects arrive at governance already clean-by-design.
Foundation 3: Build skills that actually matter
The Problem: Most organizations treat clean core as a tool problem. “We need BTP training.” “We need API documentation.” But clean core is a thinking problem.
What Works: Skill development that changes how people approach problems, not just which tools they use.
The Clean Core skill stack:
For Business analysts:
- How to write requirements that naturally lead to clean solutions
- Standard S/4 capability deep-dives
- BTP solution patterns for common business scenarios
For Developers:
- Cloud-native architecture patterns (event-driven, API-first, stateless design)
- Integration patterns that scale
- Performance optimization for distributed architectures
For Project Managers:
- How to build clean core time into project estimates
- Risk assessment for clean vs. dirty approaches
- Change management for teams transitioning from custom-first to standard-first thinking
Implementation strategy: Create specialization tracks and cross-train key people who can bridge domains. Make clean core knowledge sharing part of performance reviews.
Foundation 4: Start with strategic wins, not easy wins
The problem: Most organizations start with their simplest customizations to “build momentum.” But simple customizations don’t demonstrate real value or teach you much about clean core at scale.
What works: Choose your first clean core project based on strategic impact, not technical simplicity.
The strategic first project criteria:
- High business visibility: Something the business actually cares about and measures
- Medium technical complexity: Challenging enough to stress-test your approach
- Reusable patterns: Solutions that can be templated for similar future requirements
- Clear success metrics: Quantifiable improvements in performance or business capability
Real example: A retail client replaced their custom inventory allocation algorithm with a BTP-based solution. Not only did it work better (30% faster processing, 99.9% uptime), but the patterns they developed became the template for 12 other clean core projects. Total development time reduction: 40%.
Foundation 5: Make clean core success impossible to ignore
The problem: Clean core benefits are often invisible to business stakeholders. Faster upgrades, reduced technical debt, improved maintainability, these matter to IT but don’t resonate in board meetings.
What works: Translate clean core metrics into business language and make them visible where decisions get made.
The Clean Core scorecard:
Business metrics (for executive dashboards):
- Time-to-market for new business capabilities
- Cost per change request (before and after clean core)
- System availability during upgrade windows
- Developer productivity (story points per sprint)
Technical metrics (for IT leadership):
- Customization inventory reduction
- Customization inventory reduction
- Production incidents related to custom code
- Clean core compliance rate for new developments
Real example: A pharmaceutical client created a one-page “Clean Core Dashboard” that showed business leaders exactly how clean core was improving their ability to respond to regulatory changes. Clean core became part of their competitive advantage story. Result: 3x faster regulatory compliance implementation.
The implementation sequence that actually works
Most organizations try to boil the ocean. They want to address all their customizations, implement perfect governance, and train everyone simultaneously. That’s a recipe for failure.
Phase 1 (months 1-3): Foundation and first win
- Define your clean core charter
- Implement basic governance gates
- Complete your first strategic clean core project
- Begin skill development for core team
Phase 2 (months 4-9): Scale and systematize
- Expand governance to all new development
- Complete 3-5 additional clean core projects
- Build reusable patterns and templates
- Train extended team on clean core approaches
Phase 3 (months 10-18): Optimize and embed
- Address legacy customization backlog systematically
- Implement advanced governance automation
- Establish clean core as standard operating procedure
- Measure and communicate business impact
Phase 4 (months 19+): Innovation and competitive advantage
- Use clean core foundation to drive business innovation
- Leverage SAP's latest capabilities without customization conflicts
- Share success stories and become a clean core reference
The hard truth: This requires executive commitment
Clean core isn’t just a development practice, it’s a strategic discipline. It requires saying no to quick fixes. It requires investing in capabilities, not just solutions. It requires patience when pressure mounts.
That only works with visible, consistent executive support.
What executive support looks like:
- Clean core principles included in project charters
- Architectural decisions protected from deadline pressure
- Budget allocation for skill development and governance
- Regular communication about clean core as a competitive advantage
Without executive support, clean core becomes just another technical guideline that gets abandoned when things get difficult.
Your next steps: From reading to doing
Clean core isn’t a destination, it’s a journey. But it’s a journey that starts with the next decision you make about your SAP landscape.
- If you’re still on ECC: Make clean core a non-negotiable part of your S/4HANA strategy. Don’t migrate your problems to the new system.
- If you’re on S/4 but struggling with upgrades: It’s time for honest assessment. Every month you delay makes the transition more complex and expensive.
- If you’re ready to commit: Start with Foundation 1. Define what clean core means for your organization. Write it down. Test it against real scenarios. Then build from there.
The organizations that get this right don’t just follow clean core guidelines , they build organizational systems that make clean core inevitable.
The question isn’t whether you need clean core. The question is whether you’re ready to do the work to make it stick.
Ready to move beyond clean core theory to sustainable clean core practice? Our S/4HANA experts help organizations across the Benelux build the governance, skills, and implementation strategies that make clean core work in the real world.
The path forward is clear. The question is: are you ready to take it?
