The mechanical characterisation of existing masonry in historical structures encounters several technical dif-ficulties due to the complexity and heterogeneity of this traditional material, as well as to the need for respectful inspec-tion activities able to preserve the cultural heritage value of the building. This paper presents and discusses different Minor Destructive Testing (MDT) techniques oriented at estimating, either in-situ or in the laboratory, the mechanical properties of masonry at the level of components, such as units, tiles, and mortar joints, and at the level of the composite material. The research addresses different issues related to the execution of laboratory tests on sampled historical mate-rials, such as selection of the size and shape of specimens, different types of treatments for the sample, testing protocols, and experimental setup. The complementary use of Finite Element Method (FEM) models represents a valuable activity to provide a good understanding of the experimental behaviour exhibited by the specimens, and especially concerning the execution of non-standard laboratory tests. The possibility of in-situ MDT is explored considering techniques based on different portable instruments, previously calibrated through ad-hoc experimental programs under controlled labora-tory conditions. The research is based on a high number of tests executed at the UPC within the context of several experimental programs linked to projects of adaptive reuse of existing masonry buildings and design of green rooftops in Barcelona.