Clarissa Schönecker deals with questions of fluid mechanics in miniaturised systems. At this micro level, different physical laws prevail than on a macro scale. To measure the speed of bodies close to the surface, she uses a very sensitive optical measurement method, namely fluorescence correlation spectroscopy. In this way, she has been able to show that the deformability of the surface of a solid has significant effects on the flow around it and on resistance. She also demonstrated that bodies with elastic surfaces accelerate when dropping due to their deformability, instead of reaching a constant speed as is the case with rigid bodies. Even very small deformations change the speed significantly. Her work is relevant to a whole range of technical applications, including catalysis and circuit cooling.