D3 (Implement Interim Containment Actions)

8D discipline focused on immediately protecting customers from defective products while root cause investigation continues. Actions include 100% inspection, product sorting, shipment holds, enhanced monitoring, or product recalls. Must be implemented quickly (hours to days) and verified effective before moving to D4. Different from permanent corrective actions (D5) which address root causes. Critical when customer safety, satisfaction, or regulatory compliance is at risk.