The British Pharmacopoeia has provided official standards for the quality of substances, medicinal products and articles used in medicine since its first publication in 1864. It is used in over 100 countries and remains an essential global reference in pharmaceutical research and development and quality control. This book explores how these standards have been achieved through a comprehensive review of the history and development of the pharmacopoeias in the UK, from the early London, Edinburgh and Dublin national pharmacopoeias to the creation of the British Pharmacopoeia and its evolution over 150 years. Trade in medicinal substances and products has always been global, and the British Pharmacopoeia is placed in its global context as an instrument of the British Empire as it first sought to cover the needs of countries such as India and latterly as part of its role in international harmonisation of standards in Europe and elsewhere.