Optothermal techniques for the analysis of Cultural Heritage: introduction. Artworks, books and archaeological findings: materials and structures. Determination of the thermophysical properties of opaque (copper alloys, gildings, etc…) and semitransparent (paper, parchment, etc…) materials. Visualization of subsurface graphical features in artworks by analysing the infrared emission contrast. Determination of the thermal diffusivity of copper alloy artefacts. Characterization of thermal discontinuities in metallic compounds. Evaluation of the thermophysical properties of organic supports. Analysis of the hydrothermal denaturation process of collagen based materials.