Any communication where the sender and receiver are not engaged at the same time â emails, Slack threads, Loom videos, GitHub issues, recorded standup updates. Async communication respects the receiver's time and attention by letting them respond when they have the bandwidth to think clearly, rather than interrupting their flow. Done well, it reduces meeting load, improves decision quality (because thoughts are written down), and accommodates global teams. Done poorly, it produces endless threads with no resolution and leaves urgent items buried. Effective async communication requires explicit norms: a Service Level Agreement on response times, a clear escalation path for urgent items, and the discipline to write self-contained messages with full context rather than "can we hop on a call?"