The purpose of the present review is to describe the most widely used methods fur the estimation of lipophilicity of drugs. The relevance of lipophilicity for the biological activity of chemicals has prompted the study of techniques for the determination of this physico-chemical parameter. Although the classical octanol/water partition coefficient maintains its central role, several alternatives have been developed. In particular, the chromatographic techniques are routinely used in many laboratories. Another possibility is to calculate partition coefficients on the basis of a fragmental method. It can be shown that the chromatographic parameters are theoretically related to the partition coefficient between two immiscible phases. The good correlations between log P values and chromatographic parameters show the usefulness of the R-M and log k＇ values in estimating lipophilicity of bioactive compounds.