This chapter considers the ways in which zoos are organised and regulated under the law. Zoos and zoo organisations produce policies and standards that govern how they operate and behave. National legislation generally regulates zoos via a system of licences and inspections to ensure conformity to a range of animal welfare, public safety and other standards. The licensing systems of the United Kingdom, Sweden and the United States are considered here. In addition to national legislation, zoos are also required to comply with European laws (in the European Union), such as the Zoos Directive, and international laws such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Some individuals keep private collections of exotic animals and these are generally regulated by national or state legislation intended to ensure that animals are suitably housed, have adequate veterinary care and are being safely contained to prevent a risk to the public or the environment if they escape.