We are developing in situ transmission electron microscopy techniques for nanomaterial property measurements through combining the spatial resolution peculiar to a high-resolution TEM and precise manipulations with an individual nanoobject, e.g. its electrical biasing, resistive heating, charging, bending, stretching, peeling, and illuminating with a light of different wavelengths and pulse frequencies under a continuous control of all electromechanical, thermal and optoelectronic parameters. Thus, the true nanomaterial structure-property relationship is unambiguously established shining a new light on its application prospects.