The early architectural design stage is a typical example where traditional design tools such as sketching on paper still dominate over computer-assisted tools. Augmented reality is presented as a promising approach towards developing interaction techniques that preserve the naturalness of the traditional way of designing, while at the same time providing access to new media. Based on the analysis of user requirements and requirements for a natural user interface, a working prototype of a new interaction platform for architectural design was created. Keywords Augmented reality, Architectural design, Natural User Interface MOTIVATION In current architectural practice, preliminary designs are mostly created on paper and/or in a scale model before being converted into a representation in a CAD (Computer Aided Design) program. Only a few computer tools are available to assist designers in this early (or conceptual) design stage. The problem of introducing computer technologies at this sta...