Here we review recent progress in the development and application of molecular simulation approaches at different levels of resolution in deciphering the determinants of the emergent structural and dynamic behavior of biocondensates in terms of the underlying driving forces (Fig. ). From a fundamental equilibrium thermodynamics viewpoint, the driving force for any process is the free-energy difference between two (or more) stable states or, if the system is relaxing towards equilibrium, it follows the free-energy gradient until a stable state is reached. However, while the free-energy (or free-energy difference) is surely the most relevant quantity, it can be insightful to decompose it into the energetic (or enthalpic) and entropic contributions, ∆G = ∆H -T ∆S. At the microscopic level, everything is governed by interatomic interactions and their dynamic fluctuations, which can be probed with molecular simulations. We first review recent progress in the field of CG simulations of biocondensates and then turn to atomistic simulations. We conclude with a discussion of current challenges and possible future developments.