Proponents of justice for animals often argue that non-human animals have an interest in liberty. Furthermore, they usually claim that this animal interest in liberty is intrinsic rather than instrumental; that is to say, liberty is regarded to be good for animals in itself, irrespective of its contribution to the achievement of other goods, such as pleasure. For this reason they argue that legislating to improve welfare standards in zoos, circuses, laboratories and agriculture is inadequate. Instead, they claim that such practices are analogous to human slavery, necessarily harmful and must be abolished. In this article I refute this assertion and claim that for most animals, their interest in liberty can only ever be instrumental. In doing so I outline and reject two different arguments in favour of an intrinsic animal interest in liberty: first, that liberty is an intrinsic interest of animals because they possess preference autonomy; and second, that it is good for animals to be free, where freedom is defined as the ability to exercise one's natural functionings. I conclude that most animals do not possess an intrinsic interest in liberty because they are not autonomous in the relevant sense; that is, they cannot frame, revise and pursue their own conception of the good. If my conclusion is correct, this would have important effects on our obligations to non-human animals. I end the article by introducing some of these possible implications. Specifically, I propose that for most animals, our obligations do not consist of liberating them, and that it might be permissible to use and interfere with animals more often than other proponents of justice for animals have suggested. If this is the case, not all of the ways we keep and use animals need to be abolished. Nevertheless, many need to be reformed to improve welfare standards.