Computational methods have now evolved into sophisticated tools that are routinely used in industry and academia to develop and design drugs. The fifteen chapters of this book summarize the current status and recent developments in computer-aided drug-design methodology. The book is organized into four sections, with the first dedicated to current methods for identifying potential hits for target proteins and predicting the binding affinity between protein and ligands. The second section focuses on recent developments in ligand-based drug design methods, particularly those methods based on identifying similarities among known active compounds for use in predicting novel actives or scaffolds. The third section extends discussion toward the prediction of pharmacokinetic properties such as absorption, distribution, metabolism, excretion and toxicity of drugs. In the final section, some emerging trends in computer-aided drug-discovery are presented. The book provides a concise overview of current and emerging computer-aided drug-discovery technologies, including their successes and limitations, for developers and practitioners. It will also interest students eager to enter this exciting, highly interdisciplinary field of research.