The seismic rehabilitation of existing r.c. and masonry buildings is a topical issue in Civil Engineering. A useful technique consists in the introduction of external bracing system. This kind of intervention can be improved throughout the introduction of dissipative links, here investigated with the help of some examples.. The links are made of common steel profiles: length, geometry and its disposition are considered as design parameters. A general procedure of link-bracing optimization is proposed applying a set of identical external restraints . The adopted dissipative links consent a cheaper and effective design both in terms of ULS than in DLS: the damages are addressed in a small area permitting an easy replacement of the links in case of earthquake.