This is the updated 2023 reprint of this 1st edition. The most important part of drug discovery is pharmacological escreening for the evaluation of biological activity, efficacy and safety of novel compounds in biological systems. This book contains numerous simple and widely accepted techniques of drug evaluation in precise and concise manner. These techniques are often used in various R&D activities in the fields of pharmacology, physiology, toxicology and therapeutics. Drug evaluation/screening techniques are also used by learners to interpret the theoretical principles of drug pharmacology. The pharmaceutical industry also utilises screening techniques to evaluate the in-vivo activities of newly developed dosage forms. This book fulfils practical aspects of the curriculum of graduate and postgraduate students of pharmacy, medicine, and veterinary sciences. The sections and subsections are divided carefully for ready reference. A brief description of the drug category and evaluation techniques is incorporated for a better understanding of drug development. References for further studies and a list of abbreviations used in the text have also been given. This is an authentic VALLABH PRAKASHAN book by Vallabh Originals.