People for the Ethical Treatment of Animals (PETA /ˈpiːtə/; stylized PeTA) is an American animal rights organization based in Norfolk, Virginia, and led by Ingrid Newkirk, its international president. A nonprofit corporation with nearly 400 employees, it claims that it has 6.5 million members and supporters, in addition to claiming that it is the largest animal rights group in the world. Its slogan is "Animals are not ours to eat, wear, experiment on, use for entertainment, or abuse in any other way." Founded in March 1980 by Newkirk and fellow animal rights activist Alex Pacheco, the organization first caught the public's attention in the summer of 1981 during what became known as the Silver Spring monkeys case, a widely publicized dispute about experiments conducted on 17 macaque monkeys inside the Institute of Behavioral Research in Silver Spring, Maryland. The case lasted 10 years, involved the only police raid on an animal laboratory in the United States, triggered an amendment in 1985 to that country's Animal Welfare Act, and established PETA as an internationally known organization. Today, it focuses on four core issues—opposition to factory farming, fur farming, animal testing, and the use of animals in entertainment. It also campaigns for a vegan lifestyle and against eating meat, fishing, the killing of animals regarded as pests, the keeping of chained backyard dogs, cock fighting, dog fighting, and bullfighting. The group has been the focus of controversy, both inside and outside the animal rights movement. Newkirk and, formerly, Pacheco are seen as the leading exporters of animal rights to the more traditional animal-protection groups in the United States, but sections of the movement nonetheless say that PETA is not radical enough—law professor Gary Francione lists the group among what he calls "the new welfarists," arguing that its work with industries to achieve reform, which continues in the tradition of Henry Spira, makes it an animal welfare group, not an animal rights group. Newkirk told Salon in 2001 that PETA works toward the ideal but tries in the meantime to provide carrot-and-stick incentives. There has also been criticism from feminists within the movement about the use of scantily clad women in PETA's anti-fur campaigns and others, but as Norm Phelps notes, "Newkirk has been consistent in her response. No one, she says, is being exploited. Everyone ... is an uncoerced volunteer. Sexual attraction is a fact of life, and if it can advance the animals' cause, she makes no apologies for using it." Also, Phelps notes that some activists believe that the group's media stunts trivialize animal rights, but he qualifies this by saying, "It's hard to argue with success and PETA is far and away the most successful cutting-edge animal rights organization in the world." Newkirk's view is that PETA has a duty to be "press sluts." She argues, "It is our obligation. We would be worthless if we were just polite and didn't make any waves."

Newkirk was born in England in 1949, and raised in Hertfordshire and later New Delhi, India, where her father—a navigational engineer—was stationed. Newkirk, now an atheist, was educated in a convent, the only British girl there. She moved to the United States as a teenager, first studying to become a stockbroker, but after taking some abandoned kittens to an animal shelter in 1969 and being appalled by the conditions that she found there, she chose a career in animal protection instead. She became an animal-protection officer for Montgomery County, Maryland, and then the District of Columbia's first woman poundmaster. By 1976, she was head of the animal disease control division of D.C.'s Commission on Public Health and in 1980, was among those named as "Washingtonians of the Year."She told Michael Specter of The New Yorker that working for the shelters left her shocked at the way the animals were treated: I went to the front office all the time, and I would say, "John is kicking the dogs and putting them into freezers." Or I would say, "They are stepping on the animals, crushing them like grapes, and they don't care." In the end, I would go to work early, before anyone got there, and I would just kill the animals myself. Because I couldn't stand to let them go through that. I must have killed a thousand of them, sometimes dozens every day. Some of those people would take pleasure in making them suffer. Driving home every night, I would cry just thinking about it. And I just felt, to my bones, this cannot be right. Alex Pacheco In 1980, she divorced Steve Newkirk, whom she had married when she was 19, and the same year met Alex Pacheco, a political science major at George Washington University. Pacheco had studied for the priesthood, then worked as a crew member of the Sea Shepherd Conservation Society's first ship.[12] He volunteered at the shelter where she worked, and they fell in love and began living together, although as Kathy Snow Guillermo writes, they were very different—Newkirk was older and more practical, whereas Pacheco could barely look after himself. Newkirk read Peter Singer's influential book, Animal Liberation (1975), and in March 1980, she persuaded Pacheco to join her in forming People for the Ethical Treatment of Animals, at that point just "five people in a basement", as Newkirk described it. They were mostly students and members of the local vegetarian society, but the group included a friend of Pacheco's from the U.K., Kim Stallwood, a British activist who went on to become the national organizer of the British Union for the Abolition of Vivisection. Pacheco was reluctant at first. "It just didn't sound great to me," he told The Los Angeles Times in 1992. "I had been active in Europe ... and I thought there were just too many formalities. I thought we should just do things ourselves. But she made a convincing case that Washington needed a vehicle for animals because the current organizations were too conservative."

Alex Pacheco In 1980, she divorced Steve Newkirk, whom she had married when she was 19, and the same year met Alex Pacheco, a political science major at George Washington University. Pacheco had studied for the priesthood, then worked as a crew member of the Sea Shepherd Conservation Society's first ship. He volunteered at the shelter where she worked, and they fell in love and began living together, although as Kathy Snow Guillermo writes, they were very different—Newkirk was older and more practical, whereas Pacheco could barely look after himself. Newkirk read Peter Singer's influential book, Animal Liberation (1975), and in March 1980, she persuaded Pacheco to join her in forming People for the Ethical Treatment of Animals, at that point just "five people in a basement", as Newkirk described it. They were mostly students and members of the local vegetarian society, but the group included a friend of Pacheco's from the U.K., Kim Stallwood, a British activist who went on to become the national organizer of the British Union for the Abolition of Vivisection. Pacheco was reluctant at first. "It just didn't sound great to me," he told The Los Angeles Times in 1992. "I had been active in Europe ... and I thought there were just too many formalities. I thought we should just do things ourselves. But she made a convincing case that Washington needed a vehicle for animals because the current organizations were too conservative."

Each year, PETA selects a "Person of the Year" who has helped advance the cause of animal rights. In 2015, as Time magazine reported, the group selected Pope Francis, who took his name from the patron saint of animals, St. Francis of Assisi. Ingrid Newkirk noted, "With more than a billion Catholics worldwide, Pope Francis' animal-friendly teachings have a massive audience." Previous PETA persons of the year include Bill Clinton, Oprah Winfrey, Russell Simmons, and Ricky Gervais.