We are developing an innovative system for the performance of virtual clinical trials (VCT) of breast imaging technologies. The VCT paradigm integrates simulations of the breast anatomy, imaging systems, medical displays and model observers into a unified framework for simulating the entire imaging process, and thus performing virtual clinical trials. This approach leverages unique expertise of the University of Pennsylvania and Barco Inc. We envision VCTs having a critical role in preclinical testing of imaging devices, directing human clinical trials to the most promising devices and appropriate clinical roles. The position will involve designing innovative breast anatomy phantoms, finite-element compression models, and x-ray image simulation methods.