Although mammography is the gold standard for breast imaging, it leads to a high rate of biopsies of benign lesions and a significant false negative rate for women with dense breasts. A clinical breast‐imaging device, based on the principles of ultrasound tomography, is being developed in response to this imaging performance gap. The computed ultrasound risk evaluation (CURE) system has been designed with the clinical goal of providing fast, whole‐breast, operator‐independent imaging, capable of differentiating breast masses. In an initial assessment of its invivo performance, 50 patients were examined with CURE. The following results were demonstrated: (i) tomographic imaging of breast architecture, (ii) in‐plane spatial resolution of 0.5 mm in reflection and 4 mm in transmission, (iii) imaging of breast masses in reflection and transmission mode (sound speed and attenuation, and (iv) differentiation of breast masses was shown to be feasible. These initial results indicate that operator‐independent, whole‐breast imaging and the detection and characterization of breast masses are feasible. Future studies will focus on improved detection and differentiation of masses with the long‐term goal of improving the specificity of breast exams. [The authors acknowledge financial support from the Karmanos Cancer Institute and the NIH (grant R43 CA108072‐01).]