This is an extensively re-written second edition of a well regarded and much cited text on the issue of animal protection. It remains the only text to combine an examination of the philosophy and politics of the issue. Its central argument is that the philosophical debate is central to an understanding and evaluation of the substantive issues involving animals and the nature of the movement for change. The book has been thoroughly revised to include major theoretical and empirical developments. Specifically, the "second generation" of animal ethics literature is examined in detail, and attention is paid to the campaigns and public controversy over the export of live animals and the use of animals in research, the impact of genetic engineering on the welfare of animals and the latest developments in the controversy over hunting.