Eins, Zwei is an interactive space for rhythm and motion. With this experimental human-machine interface, visitors can shape music through movement and their individual perfor mance. This happens in a private environment that focuses on the sonic and physical experience. In this space, two very different parties—the human dancer and a computer program—try to communicate with each other through contrasting input and output channels. The outcome is an ephemeral audio-physical expression of the successes and failures of this communication. And only one of the parties will care about this result.