The presence of impurities, even in small amounts, may affect the efficacy and safety of pharmaceuticals. The methods for detecting and controlling them are subject to continuous review and improvement. Characterisation of impurities is a crucial aspect of drug development and approval, and is central to quality control. This book provides a source of reference on the techniques available for accurate identification and quantification of drug impurities, and it brings together all the relevant disciplines within one volume for the first time.