Description: Cosmological simulations have become an indispensable tool for studies of supermassive black holes, galaxies, clusters of galaxies, the intergalactic medium, and large-scale structure. Such simulations show that a small number of simple physical laws can give rise to an amazingly rich phenomenology, in remarkable agreement with many aspects of that observed. The continuing increase in the speed and memory of computers and improvements in algorithms allow us to perform ever more detailed simulations to help guide the interpretation of complex astronomical phenomena. Although the results of recent cosmological simulations are impressive, their reliance on highly simplified models for unresolved “sub-grid" processes precludes a full understanding. Fortunately, simulations zooming into a small number of objects are able to move the transition to subgrid physics to smaller and smaller scales. Simulations are beginning to include radiation transport, magnetohydrodynamics, cosmic rays, a cold interstellar phase, and (time-dependent) chemistry, though not all at once. At the other end of the spectrum, dark matter only simulations, semi-empirical (e.g. abundance matching) models and semi-analytic models are quickly increasing in size and precision. Such simulations remain critical for the preparation and interpretation of cosmological surveys of large-scale structure. In this regard the modelling of alternative cosmologies is making great strides. Aim: The aim of this workshop is a strengthened synergy between the three types of cosmological simulations: large-scale collisionless models, optionally combined with semi-analytics, hydrodynamical simulations of representative volumes, and zooms of individual objects that include more physics. The workshop will build on previous meetings organized by the Virgo consortium for cosmological supercomputer simulations. Other important goals of the workshop are to train young researchers, to make progress with the existing international Virgo projects, to initiate new collaborations for the analysis of the simulations, and to come up with ideas and proposals for future simulation projects.