We have created a modified technique of localization biopsy of the breast that more easily identifies the position of the wire tip after placement and before biopsy. After wire placement, metallic skin markers are placed on the nipple and wire entry site. The patient is then positioned on a roentgenography table in the same position to be used during biopsy. A supine roentgenogram of the breast is obtained. At the time of the biopsy, this roentgenogram is aligned with the corresponding markers on the skin of the patient and the position of the wire tip is noted. A curvilinear incision along Langer's lines can then be made at that site. This procedure was used in 53 consecutive biopsies of nonpalpable mammary lesions. In all instances, the biopsy incisions were independent of the wire insertion sites and in each instance, the lesion was excised in a single specimen. Compared with other techniques, our method is simple, inexpensive, requires no special equipment and results in only a minimal increase in radiation dose to the breast (50 millirad). The decrease in the amount of tissue dissection without decreasing accuracy afforded by our technique can improve compliance with the American Cancer Society's recommended surgical guidelines for breast preservation therapy.