Understanding mechanical, electrical, thermoelectric, optical, optoelectronic and photovoltaic properties of nanomaterials, in particular on the individual structural level, is of key importance as far as their effective integrations into modern technologies are concerned. However, in the vast majority of cases, these property measurements have been performed by means of instruments with no direct access to the nanomaterials’ atomic structure, its crystallography, spatially-resolved chemistry and existing point and linear structural defects. This fact largely limits the relevance of the collected data because all particular structural features of a nanoscale object prior, during and after its testing are typically hidden. Therefore, the acquired results could not be directly linked to a particular nanostructure, its internal morphology and defect structure. Thus a wide scatter in the reported data has been common between various samples and research groups. Till now this drawback has greatly confused practical engineers and technologists and led to many uncertainties in regards of nanomaterials’ real industrial potentials.
 
In this contribution I demonstrate the full usefulness of newly designed by us in situ high resolution transmission electron microscopy (HRTEM) probing techniques for diverse property analyses of individual inorganic nanotubes, graphene-like nanosheets, nanowires and nanoparticles. Elasticity, plasticity, fracture strength and toughness, electrical conductance, thermal gradients, photocurrents, photovoltages and spatially-resolved cathodoluminescence are now may accurately be measured inside HRTEM, while employing piezo-driven nanomanipulators and/or optical fibers inserted into the microscope column.