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The development of the basis for the displacement-based seismic design of unreinforced masonry (URM) structures is the ultimate objective of the present research project, which should be seen as the first step in an initiative to investigate the limits of the displacement capacity of contemporary URM walls. After a thorough survey and assessment of previous experimental and theoretical studies on the area of displacement capacity of URM walls, an experimental programme consisting of 10 static-cyclic shear tests on full-scale unreinforced clay and calcium-silicate masonry walls was carried out. The experimental programme aimed primarily at studying the effects of unit type, pre-compression level, aspect ratio, boundary conditions and size on the displacement capacity of contemporary URM walls. All the specimens (regardless of their failure mode) exhibited limited displacement capacity. The drift ratio capacity of the specimens that failed in shear was particularly small so that the mean value of the drift ratio capacity was 0.27% with a COV of 12%. However, the specimens that failed in flexure and in sliding-flexure combination exhibited larger drift ratio capacity, i.e. 0.32% and 0.62%, respectively. The test results showed that the drift ratio capacity decreases as the pre-compression level increases or as the aspect ratio decreases. Furthermore, they indicated a possible reduction in the drift ratio capacity in the case of an increase in the height (size effect). A direct relation was also found between the drift ratio capacity and the shear span, which is controlled by the boundary conditions. In addition, the calcium-silicate specimens showed slightly …