BACKGROUND Technical defects are a potential cause of peri-operative strokes following carotid endarterectomy (CEA) by either the eversion technique or the standard method of longitudinal arteriotomy with or without patch closure. OBJECTIVE A non-randomised retrospective study was undertaken to assess the value of angioscopy for the identification of technical errors following CEA and to compare those detected following eversion and standard endarterectomy with patch closure. METHODS Intra-operative completion angioscopy was performed following 110 CEAs (56 eversion, 54 standard). Angioscopy was omitted in 5 patients because of technical problems (2) or extreme shunt dependency (3). RESULTS Significant technical defects were identified and corrected in 10 cases (9%) and were equally distributed between the eversion and standard procedures. There was no peri-operative stroke or death in this series. CONCLUSIONS Significant residual defects may occur after CEA by either technique. Angioscopy allows their correction peri-operatively and has the potential to reduce peri-operative stroke.