Over the past fifty years, molecular simulation has emerged as a useful tool for providing microscopic insight into a variety of chemical systems and processes. There are two main particle-based simulation techniques – molecular dynamics, which uses deterministic equations of motion integrated over small time steps to evolve the system, and Monte Carlo sampling, which uses a Markov chain to construct a stochastic sequence of system configurations. Molecular dynamics can provide insight into time-dependent and time-averaged properties of the system, whereas Monte Carlo simulations provide ensemble-averaged properties. Both techniques have been extensively used to investigate solubility in different chemical systems.