Root Cause Analysis is the discipline of moving from symptom control to verified causal understanding. The goal is not to find someone to blame. The goal is to explain, with evidence, why the problem occurred, why it escaped detection, and what system changes are required so it does not return.
This hub organizes the site’s RCA material from simple frontline tools through more formal containment, corrective action, and AI-assisted investigation methods.
Best Guides
Lean 5-Why Root Cause Analysis
Use repeated why-questioning to peel back symptoms and expose process-level causes.
Fishbone (Ishikawa) Analysis
Organize possible causes across people, machine, method, material, measurement, and environment.
Pareto Analysis
Prioritize the vital few causes, defects, or categories that deserve the first deep investigation.
8D Problem Solving
Work through containment, team structure, root-cause validation, corrective action, and closure.
CAPA Process and Effectiveness
Connect root-cause findings to formal corrective and preventive action systems.
AI for Root Cause Analysis
Use AI to accelerate evidence synthesis without replacing human verification at the gemba.
Project SENTINEL Case Study
See a full problem-solving story from symptom, to validation, to systemic replication logic.
Related Calculators and Tools
Lean 5-Why Tool
Guide a user from problem description into sequential why questions and a likely root cause path.
Hypothesis Testing Quick Tester
Validate suspected cause-effect relationships with statistically defensible before/after comparisons.
Related Templates
Lean 5-Why Template
Document the why chain, evidence trail, and completed root-cause register in a reusable workbook.
8D Template
Use the full D0-D8 workbook when escalation, containment, validation, and cross-functional accountability are required.
Suggested Learning Path
- Start with Pareto analysis to choose the right problem.
- Use 5 Why for simple, focused investigations close to the point of work.
- Add Fishbone analysis when multiple categories of causes need structured exploration.
- Move into 8D when customer impact, repeat failure, or cross-functional coordination raises the stakes.
- Learn CAPA so findings turn into governed system action rather than one-off fixes.
- Use AI-assisted RCA after your data and governance foundation is strong enough to support it.
- Study Project SENTINEL to see how the pieces work together in practice.