© 2015 Royal Australasian College of Surgeons. Background: A significant proportion of breast cancers present as impalpable lesions requiring radiological guidance prior to surgical excision, commonly by hook-wire placement. Complete lesion excision is an essential part of treatment, and re-excision may be needed to ensure this and minimize local recurrence. We explore a 1-year audit of re-excision of hook-wire-guided excisions in two large public breast units in Western Australia and define factors associated with the requirement for re-excision. Methods: A retrospective review of wire-localized wide local excisions for early breast cancer in 2009 at two tertiary breast centres in Western Australia. Results: Of 148 localized lesions, 44 (30%) underwent re-excision. The only significant preoperative finding was the location of tumour in the breast. The intra-operative specimen radiograph provided useful information that influenced re-excision. Smaller (≤5mm) and larger (>20mm) tumours on final pathological size were more likely to undergo re-excision as well as a larger difference in actual size to predicted size. The presence of ductal carcinoma in situ (DCIS) increased re-operation, as did multifocality. Conclusion: This study highlights factors that should make the surgeon more cautious for re-excision. Suspicion of DCIS, especially at the periphery of tumours, and a central tumour location increase risk. Lesion localization techniques play an important role in minimizing risk while maintaining cosmesis.