Design a global load balancing strategy for a multi-region application.

Multi-layer approach: DNS-based (Route 53, Cloudflare - latency/geo routing, health checks), anycast (edge distribution), regional load balancers (AWS ALB/NLB per region). Considerations: latency measurement (latency-based routing), health checking (global monitoring), failover (automatic region failover), data locality (keep requests near data), session affinity (if needed). Active-active vs active-passive by region. Combine DNS (seconds) with anycast (instant) for optimal failover speed. Monitor: synthetic probes from multiple locations.