The choice of appropriate repair and/or retrofitting techniques for an earthquake damaged building always requires: 1) a preliminary assessment of the current state of the building, to understand its stability and its intrinsic robustness, to determine whether the repair and strengthening is viable in terms of delivering a safe building; 2) a detailed design of the strengthening and definition of the construction sequence to ensure that the end product performs as assumed in the assessment phase; 3) an assessment of the materials, skills, logistic and economic resources available to implement a specific repair or retrofitting system. The present document focuses on strengthening methods for masonry structures. It provides a review of available sources in literature useful to support point 1 and provide a number of different suitable methods to fulfil point 2. To address point 3 the reader should review the specific geographic, socio-economic and cultural conditions within which the operations are conducted and determine whether the implementation is feasible to a level of quality which will assure the delivery of a safe building. The remainder of the document contains an annotated bibliography, the key advantages and drawbacks associated to the most common strengthening techniques for masonry buildings and a set of conclusions summarising the fundamental steps for a successful strengthening process.