Orchestration patterns are proven architectures for multi-agent coordination. Sequential processing handles dependencies: A completes before B starts. Parallel execution maximizes throughput when tasks are independent. Hierarchical orchestration uses supervisors to decompose, delegate, and synthesize. Debate patterns have agents argue positions to converge on better answers. Handoff routing dynamically assigns work based on content. Magentic orchestration uses typed function calls for structured agent communication. Each pattern has trade-offs—knowing when to use each is the core skill of orchestration design.