The Reality Editor is a system that supports editing the behavior and interfaces of socalled “smarter objects”, i.e. objects or devices that have an embedded processor and communication capability. Using augmented reality techniques, the Reality Editor maps graphical elements directly on top of the tangible interfaces found on physical objects, such as push buttons or knobs. The Reality Editor allows flexible reprogramming of the interfaces and behavior of the objects as well as defining relationships between smarter objects in order to easily create new functionalities. This paper describes the different functionalities of the Reality Editor and presents several examples.