This study aimed at producing a report (inventory) on stabilization / repair / strengthening materials, methods and technologies used for the structural restoration of structures including cast iron, wrought iron and steel members. A detailed literature survey was carried out by reading as much document as possible using different database including UPC library and after all the courses studied throughout this advanced master study it may be concluded that regardless of the technique decided to be applied in a restoration project, it is very important that any repair or strengthening must be based on a correct diagnosis of the problem by determining the real cause of the observed defects, and if the cause is still active by eliminating it. Otherwise the repairs will be short-lived. There is a parallel in the field of medicine: any treatment must be preceded by a correct diagnosis.