The Analytical Methods Committee of the Royal Society of Chemistry has for many years been involved in national and international efforts to establish a comprehensive framework for achieving appropriate quality in chemical measurement. This handbook attempts to define robust procedures that ensure the best use of resources and enable laboratories to generate consistent, reliable data. Illustrated with worked examples, it is a guide to current best practice and establishes a control framework for the development and validation of laboratory-based analytical methods. Attention is given to the sample, method chosen, instrumentation, personnel and calculation used, ensuring that each is fit-for-purpose.