In this paper the Authors discuss about femoral anastomotic pseudoaneurysms. They throughly consider the etiopathogenesis of this late complication of arterial prothesic surgery, pointing out the different hypothesis currently discussed. Particularly from this analysis it can be concluded that the choice of appropriate prothesic grafts and the weakness of an eventually endarterectomized arterial wall are the principal determinants in causing pseudoaneurysms. Between the different therapeutic choices the opportunity of an interposition graft is underlined, except for (rare) cases when an extra-anatomic bypass must be preferred.