The current standard of treatment for non-palpable breast cancers is wire-guided localization (WGL). WGL has its drawbacks and alternatives such as radio-guided surgery (RGL) and intra-operative ultrasound (IOUS) have been developed. The clinical effectiveness of all forms of RGL has been assessed against WGL in previous systematic reviews and meta-analyses. We performed the first systematic review and meta-analysis of IOUS in the management of non-palpable breast cancers.