Being able to focus, hold, and work with information in mind, filter distractions, and switch gears is like having an air traffic control system at a busy airport to manage the arrivals and departures of dozens of planes on multiple runways. In the brain, this air traffic control mechanism is called executive functioning, a group of skills that helps humans to focus on multiple streams of information at the same time, and revise plans as necessary. Acquiring the early building blocks of these skills is one of the most important and challenging tasks of the early childhood years, and the opportunity to build further on these rudimentary capacities is critical to healthy development through middle childhood and adolescence. This paper explains how these lifelong skills develop, what can disrupt their development, and how supporting them pays off in school and life.