PhysiCAD is an interface for using physical gestures to build digital 3D models. While the learning curve associated with typical 3D modeling programs can be steep, PhysiCAD makes this powerful tool fun to use and accessible to those without prior training. Using a hand tracking camera and custom algorithms for gesture recognition, PhysiCAD allows users to create geometric and abstract forms with intuitive hand motions. This platform presents a new workflow for ideation and rapid digital prototyping, fosters efficient collaboration and presents new opportunities for education. Designers and non-designers alike will delight in the experience of building sculptural forms with the wave of a finger.