We have developed a CCD-based, high performance, filmless imaging system for stereotactic biopsy procedures in mammography. The CCD camera is based on a 1024 X 1024 pixel format, full-frame, scientific grade, front-illuminated, MPP mode CCD, directly coupled to an X-ray intensifying screen via a 2:1 fiber optic reducer. The CCD is cooled to -10 degree(s)C, and is digitized in slow-scan, correlated double sampling mode at 500 Kpixels/second with 12-bit contrast resolution. X-ray images acquired with the system are processed and displayed on a high resolution monitor within 20 seconds of exposure. System design and specifications will be described, and evaluation of physical performance characteristics will be discussed. The system has been used in over 100 stereotactic breast biopsy procedures to date, and has been shown to significantly improve the speed and accuracy of the biopsy procedure, due to the near real-time acquisition and display of x-ray images. Initial results also indicate that the fiber optic coupled CCD-based imaging system provides superior detectability of low contrast breast lesions and microcalcifications at lower patient dose, as compared to conventional film-screen detectors.