To prevent accidents and damage, detection of materials failure ahead of of the breakdown of a construction is necessary. Especially the material failure in composites like particle or fiber reinforced polymers is a complex process. One solution is to fill the polymer matrix with a material which indicates the mechanical states of the polymer. E.g., a molecular switch which changes its color by different external stimuli like mechanical stress or softening due to temperature. For demonstration a polymer matrix that has shape memory abilities is filled with a very low filling factor of spiropyrane molecules. The colour change of the molecules indicate a the mechanical transformation of the polymer at elevated temperatures. In addition, ZnO microparticles can also be used for failure reporting due to its photoluminescence of surface defects that occur either at higher temperatures or under mechanical damage. In this video scientists from the functional nanomaterials group at the materials science institute of Kiel University will give a demonstration of the unique properties of all the three components mentioned.