Interventional procedures, whether markings or core biopsies, are very important for clarifying non-palpable breast lesions. Both at present as well as in future--in the age of breast screening--such methods must be used more and more. Although breast screening is not carried out on an organized basis in our country, it is gaining importance. Currently there is a covert screening in progress and women are availing this facility to an increasing extent. Various organisations including the press and audio-visual media have arisen the interest of the population. An increase in diagnostic studies is being flanked by an increase in surgical activity. As a result, on the one hand a larger number of small carcinomas as well as benign lesions are being operated. This has brought the cost-bearers, i.e. all of us, to the limits of what can be done. Surgery costs money. One solution to the problem is preoperative marking which is used in all patients suspected of carcinoma, and the other is core biopsy which is used in lesions that appear benign on X-rays. Radiologically benign lesions are not histological diagnoses. Although a well trained radiologist will make the correct diagnosis in 95 to 98% of cases, the possibility of error is still 2 to 50%. In the light of this knowledge, it would appear logical to operate all apparently benign lesions. However, a more intensive use of bioptic procedures is a solution to this problem. To compare costs: Surgery for clarification of a lesion involves a hospital stay of about 3 days while bioptic studies can be carried out on an outpatient basis. Besides, surgery costs 2 to 3 times more than bioptic studies, depending on the hospital and the bioptic material used. A core biopsy needle costs about two-thirds the price of a rotating cannula. However, it should be emphasized that core biopsy is not a method of treatment and will never be one. It should remain a diagnostic procedure, although small lesions may well be aspirated by this method. The ABBI systems is intended to be a therapeutic method. At present, no final statement can be made about the utility of this procedure.