Conclusions Adhesive bond strength of dissimilar material single-lap joints subjected to various kissing or weak bond defects was evalu- ated using an experimental mechanics–based DIC technique. A baseline sample (i.e., without contamination) was also considered. DIC technique detected changes in the normal strain (εyy) contour map of the contaminated specimens at relatively lower load levels. These load levels correspond to 15% of the failure load for the silicone and hydraulic oil con- taminated sample and around 30% of the failure load for the polyvinyl alcohol (PVA) contaminated sample. Kissing or weak bond regions were characterized by the negative strains in the strain maps. Due to the load application, these can be attributed to the localized disbonding at the bonding interface. 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