The usual views of air traffic — a single plane in the sky, several planes on approach, even the route map in the back of the in-flight magazine — are deceptive. The truth is that air traffic (and its counterpart, maritime traffic) is a big, messy, complex, ever-evolving morass where this morning’s anomaly is this afternoon’s status quo. Naturally, understanding this mess is increasingly crucial to applications from airspace management to economic planning. I will illustrate some of the complexity that makes traffic analysis difficult and will discuss Tracktable, a suite of algorithms and tools under development at Sandia that has yielded insight into the lower- and higher-level patterns present within large traffic data sets.