The “Theory and Simulation of Solar System Plasmas” session solicits presentations of the latest results from theoretical investigations and numerical simulations in space plasma-physics from microscopic to global scales, in comparison with experiments and observations in the heliosphere: at the Sun, in the solar corona, in interplanetary space and in planetary magnetospheres. Each year a topic of special interest is chosen as a focus of the session. For 2020 this focus will be on space plasma turbulence and its consequences for particle acceleration and plasma heating. There are challenging questions in fundamental solar system plasma physics which require the analyses of huge amounts of data, in particular of the particle kinetics. Machine learning techniques have to be used. We further encourage presentations of theory and simulation results relevant for to current, forthcoming and proposed space missions, notably MMS, Parker Solar Probe, Bepi Colombo and Solar Orbiter.