Tom Regan is an American philosopher known for his work in animal rights and ethics. He is best recognized for his book, "The Case for Animal Rights," published in 1983, where he argues that animals have inherent value and deserve moral consideration. Regan's philosophy is rooted in the belief that sentient beings should not be treated merely as means to an end. Regan is also a prominent figure in the animal rights movement, advocating for the protection of animals from exploitation and harm. His ideas have influenced both academic discussions and practical approaches to animal welfare, contributing to the broader discourse on ethics and animal liberation.