Science and Education Publishing American Journal of Modeling and Optimization 1 3 2013 12 15 How to Calculate Binding Constants for Drug Discovery Studies 61 70 EN María J.R. Yunta Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense, Madrid, Spain AJMO2013137 10.12691/ajmo-1-3-7 2013 09 05 2013 10 07 2013 12 15 Free energy calculations to predict binding ability of molecules to receptors are a main subject for drug design. A wide range of theoretical methods has been applied to the calculation of binding constants. This mini-review seeks to identify such methods to better achieve correct predictions for drug candidates.