The National Breast Screening Programme had dramatically impacted surgical practice. Up to 50% of all newly diagnosed cancers are now impalpable creating increased demand for image-guided localisation. Wire-guided localisation (WGL) is the current gold standard, but USS-guided localisation by radiologists is a well-documented and effective technique. Increasing numbers of surgeons are proficient in using ultrasound and may be as accurate as radiologists in localising lesions intra-operatively. Of 68 patients with screen-detected impalpable lesions referred to one surgeon in our unit between January 2005 and February 2006, 32 had mass lesions, which were well seen on ultrasound and underwent intra-operative USS-guided localisation performed by a surgeon. All lesions were correctly identified and 87.5% (n=28) were fully excised. Those lesions not fully excised were lobular cancers. Intra-operative sonographic localisation performed by surgeons is an accurate and effective technique. It may produce less patient anxiety and discomfort than WGL and allow more effective and efficient use of resources and theatre time.