In the presented thesis I defend the claim that all sentient animals should have legal rights. The arguments I offer in support of this claim are based on the moral and legal status of animals. I try to show that all sentient animals are ends in themselves for the reason that they are beings with their own interests, and their capacity for having welfare and the fact that there are things that are good and bad for them impose certain duties on us. Our duties should be reflected in the law, that is – animal interests should be protected by the legal means. I argue that some animals are moral subjects and because of their admirable ability to act for moral reasons and show moral concern towards their counterparts they intrinsically deserve the highest level of protection of their vital interests that is – they deserve legal rights. I also contend that all sentient animals who are moral patients should have legal rights for the same reason human infants and profoundly mentally impaired adults are granted some basic legal rights.