Surgical excision biopsy is considered by many to be the "gold standard" for the diagnosis of breast lesions. Fine needle aspiration biopsy is used by some radiologists and other physicians in an attempt to diagnose breast lesions nonsurgically. To overcome the drawbacks associated with both of these methods, the author and his coworkers have developed the image-guided automated large-core breast biopsy method.All biopsies are performed using either a dedicated, prone stereotactic device or high-resolution near-field ultrasound equipment for needle guidance. A "long-throw" (2.3 cm) automated core biopsy device fitted with a 14-gauge needle is used to acquire five or more core samples from each lesion for histologic evaluation.The ability of percutaneous, image-guided, large-core breast biopsy to provide the correct histologic diagnosis of a breast lesion is equivalent to open surgical biopsy. The cost of large-core breast biopsy is one half to one quarter that of surgical biopsy. No adverse cosmesis or mammographic pseudolesion results.In an era of increasing cost restraints in health care, it is important to identify means by which the level of patient care can be maintained or improved at lesser cost. Percutaneous large-core breast biopsy provides that opportunity in the diagnosis of breast disease and should prove to be a cost-effective, reliable, and expedient alternative to surgical biopsy.