models.

To describe the solubility related aspects in drug discovery and development with overview on factors affecting solubility of drug along with the special focus on the practical approaches of solubility determination. The solubility is essential factor in the initial stages of drug discovery and development. The determination of solubility gives an idea about the drug response prediction. The poor solubility results in ineffective response in experimental design. The use of solubility data in appropriate setting is very important before screening of drug. The biopharmaceutical classification system is of pH dependent used to classify drugs on the basis of pH dependent solubility and permeability. This article outlines solubility aspects in drug discovery and development with factors that influences solubility and methods to determine the solubility of drug with different models developed to predict solubility.  Investigators are constantly searching for different approaches to determine and predict the solubility of drug. But still there are several work is being done by the investigators to increase the efficiency and accuracy to determine the solubility.