In this paper we describe the Augmented Reality (AR) authoring system "PowerSpace" which allows fast and comfortable generation of AR worlds. The system presented uses the functionality of a 2D presentation program (Microsoft PowerPoint) as the basis for the composition of 3D content. An MS PowerPoint export is used to generate an XML-based extensible description of a presentation. This description is enriched by 3D content with the help of an editor, which is also part of the PowerSpace system. The content of this presentation is finally converted into 3D scenes and is used in an AR-Viewer. Keywords Augmented Reality, Authoring, PowerPoint, PowerSpace, 3DUI