The transformation of animal hide to create derivative products has been a process connected with mankind since the earliest days. The city of Igualada has a long tanning tradition, and the Igualada Leather Museum presents the process from pre-industrial tanneries (Cal Granotes) up to the mechanisation of the process. This publication deals with various aspects connected with the leather industry: the raw materials, resources, industrial processes, environmental impact and the treatment of general waste.