The mathematical description of many-particle systems is a fundamental and challenging problem. At the microscopic level, particle interactions can be modeled with very large systems of ordinary differential equations. This approach can be impractical due to the very large dimension of the systems. Mean field models based on partial differential equations thus arise to describe the collective behavior of a large number of particles. Depending on the spatial and temporal scales, as well as the heterogeneity among particles, PDEs of different types and dimensions emerge. At the mesoscopic level, effective models are kinetic equations - including the Vlasov, Boltzmann, Landau equations - while at the macroscopic level we have continuum equations (for example, the Euler and Navier-Stokes equations). Beyond common mathematical challenges, microscopic, kinetic and fluid equations share a deeper link: Fluid equations can be obtained as a limit in certain asymptotic regimes from kinetic equations which, in turn, can be obtained by limits from microscopic models. This workshop aims at bringing together researchers working in these three connected areas from an analytical and computational perspective. These areas have seen dramatic progress over the last decade, and the methods and problems in each field are becoming highly relevant to the other fields. The meeting will showcase the most recent breakthrough results and promote interactions among communities and cross-pollination of techniques and mathematical methods.