The runway complexes of major airports are among the scarcest resources of today’s international air transport system and, barring a drastic change in the landing and takeoff requirements of commercial aircraft, will continue to be so in the foreseeable future. New runways are very expensive to build, require great expanses of land, and most importantly have environmental and other impacts that necessitate long and complicated approval processes with uncertain outcomes. It is not surprising therefore that one of the most “mature” areas of transportation science deals with the modeling of runway operations and, more generally, airside operations. The products of this work include both analytical (“mathematical”) models and simulation tools.