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description: Use when analyzing a problem with multiple potential contributing factors
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# Root Cause Analysis (Fishbone / Ishikawa)

Use a fishbone diagram to systematically explore all potential causes of a problem across multiple categories, ensuring no contributing factor is overlooked.

## Steps

1. **State the problem** — Write the effect or problem at the head of the fishbone.
2. **Define cause categories** — Draw major branches for standard categories: People, Process, Technology, Environment, Materials, Measurement (adapt as needed).
3. **Brainstorm causes per category** — For each branch, list all possible contributing factors. Ask "why" to add sub-causes.
4. **Identify the most likely root causes** — Evaluate each cause for evidence and impact. Circle or highlight the most probable contributors.
5. **Define corrective actions** — For each root cause, propose a specific, measurable countermeasure.

## Output Format

A fishbone diagram with the problem at the head, 4-6 category branches with causes and sub-causes, highlighted root causes, and an action plan table with columns: Root Cause, Corrective Action, Owner, Timeline.