The mini-symposium aims to present challenging problems of multiscale description of various phenomena including polymeric fluids,collective behaviour,to name a few.There are different approaches to such problems-either through kinetic equations,modelling of the microstructure by the stochastic partial differential equations or by capturing microscopic quantities in terms of averaged macroscopic ones.Our aim is to present some of these approaches and the recent studies,both from the point of view of mathematical analysis and numerical results.