This study extends quality management from an individual company perspective to a supply chain perspective. We propose a concept of supply chain quality integration (SCQI) that consists of internal, supplier, and customer integration for quality improvement, and develop a model that specifies the relationships among competitive hostility, the organization-wide approach to quality, three types of SCQI, and quality-related performance. We test the model using data collected from 291 high-performance manufacturing plants from ten countries. The results indicate that competitive hostility has a positive effect on the organization-wide approach to quality, and that both have positive effects on SCQI. In addition, internal quality integration significantly enhances external quality integration with both suppliers and customers. Further, internal quality integration significantly improves all quality-related performance (i.e., product quality, cost, delivery, and flexibility), and both supplier and customer quality integration significantly improve cost performance. Whereas customer quality integration significantly improves delivery performance and supplier quality integration significantly improves quality performance, only internal quality integration can improve flexibility performance. The findings reveal how different types of SCQI are related to quality-related performance and highlight internal quality integration as a core strategic resource for quality improvement. As such, they provide important managerial insights for supply chain quality managers to improve quality-related performance.