This book offers a state-of-the-art view of leather making, based on the scientific principles underpinning the technology. In particular, it contributes to the understanding of the modern leather industry, allowing practitioners to make judgements about day-to-day problems in the tannery and how change can be applied in a predictable way. Major themes running through the book are the economics and environmental impact of leather making and how these will ensure the sustainability of the industry. This second edition of Tony Covington’s Tanning Chemistry is a revision, update and extension in collaboration with a new co-author, Will Wise. The update reflects the advances made in the past decade, including a discussion of the impact of new information concerning the chemistry of sulfide. The original chapters have been re-organised and new chapters on novel modes of reagent delivery and the principles of finishing are now included. Enzymology is addressed as a separate topic, as are environmental impact and the future of leather. The book will be useful to all those involved in the supply chain, from farm, through students, chemical suppliers and tanners, to leather goods brands. Leather science is the key to understanding leather technology, to make it work, to make it work better and to keep it ahead of the competition.