The purpose of the 4th meeting of the liquid section of the European Physical Society was to contribute to a better communication between different scientific communities of fundamental and applied sciences dealing with random structures and processes. This should lead to an awareness of the relationship between geometries at different scales and physical behaviors. The papers presented here show how one can go from a microscopic description to a phenomenological one by using hydrodynamical treatments and statistical ones (when disorder is present) as the mediators in this process of change of scales. This permits one to change from the microscopic description of a spreading drop at the nanometer scale to the study of a foam or of the wetting in random materials. In the same way, one can go from the microscopic properties at the interface of two fluids to the macroscopic dispersion behavior or from the interaction between two particles (or between a particle and a surface) to the rheology of a suspension.