Water solubility is an important molecular property for successful drug development as it is a key factor governing drug access to biological membranes. There have been a number of review articles addressing computational models to predict water solubility with emphasis on the accuracy of the various prediction methods. This paper briefly reviews the available models and focuses on the value which can be extracted by comparing calculated and measured solubility, discusses the potential and limitations of the main computational approaches, and provides guidelines as to when to trust the computed value.