Organic inorganic hybrid halide perovskites (PSCs) have emerged as a promising class of materials for solar cells. Thanks to their remarkable optical properties such as high absorption coefficient, tunable bandgap, high charge carrier mobility and low exciton binding energy, PSCs facilitate high power conversion efficiencies (PCE). Indeed, the PCEs of PSCs have rapidly risen since 2009 from 3.8% to a certified 25.6% [1] in 2021. Nevertheless, the PSCs have not yet conquered the market due to their limited long-term stability of the perovskite phase. Simulation assisted methods which could reliably predict relative finite temperature stabilities of the competing phases (e.g. δ-phase), as well as allow the treatment of sufficiently large samples (and time scales) would give important guidance in the design of long-term stable perovskite systems for PSCs. While full first-principle methods (e.g. density functional theory) are limited by the simulated system size and feasible timescale, classical molecular dynamics simulation overcomes these limitations. Not surprisingly considerable research efforts have been directed at the development of accurate forcefields (FFs) for these systems. One of the first FFs for perovskites was developed by Mattoni et al. [2,3] for methylammonium-lead-iodide (MAPbI₃) and later adapted in different flavors for describing the interaction of MAPbI₃ with water [4] and capturing MAPbBr₃ as well as mixed halide MAPbI_3-xBr_x compounds [5]. Recently, a polarizable FF has been introduced [6] that is able to describe the δ-phase of CsPbI₃, however still not yet its transition to the (photovoltaically active) perovskite phase. Clearly, the simultaneous description of non-perovskite and perovskite phases along with their phase transition(s) is still nowadays a challenge for which hardly any FFs have been developed so far. This talk will present an overview and recent advances of the developments of such forcefields in that field.