In Defense of Animals: Fighting for Animals, People and the Environment Since 1983.

Who We Are

With your help, In Defense of Animals has become an international animal protection organization with over 250,000 valued supporters and a 40-year history of fighting for animals, people, and the environment. We accomplish our mission through education and campaigns, as well as sanctuaries and hands-on animal rescue facilities in India, Korea, and rural Mississippi. Our main headquarters are established in Marin County, California.

IDA Founder Dr. Elliot Katz along forges ahead with his supporters to advocate for the obvious need for animal rights

IDA Founder Dr. Elliot Katz along forges ahead with his supporters to advocate for the obvious need for animal rights

Our History

In early 1983, veterinarian Dr. Elliot Katz was contacted by animal activists and discovered scandalous conditions inside UC Berkeley’s animal laboratories — an event that changed animal protection history. Living in cramped and filthy facilities, animals were sick and dying while campus veterinarians were prevented from providing treatment to those in need. Dr. Katz formed Californians for Responsible Research, which filed a lawsuit against USDA, forcing them to issue a cease and desist order against UC Berkeley. Ultimately, Berkeley was fined $12,000 for violating the Animal Welfare Act. Californians for Responsible Research was renamed In Defense of Animals, and for nearly four decades years it has become a force to reckon with — foremost in animal advocacy. Dr. Katz passed away in March, 2021, and will be remembered as an animal rights trailblazer.

Dr. Marilyn Kroplick, a medical doctor and psychiatrist, has served as President since 2011. She guides the organization with her unique knowledge and a fresh approach as a visionary animal protection leader.

The Need

Sadly, animal suffering and exploiting is the status quo. Millions of animals around the world suffer as objects of entertainment, food, experiments, clothing, or throwaway creatures pushed out of habitat by human expansion.

Most people denounce animal suffering. In Defense of Animals has developed a unique approach to sow seeds of compassion to end cruelty. We strive to instill a new balance, in awaken awareness, and foster harmony — between animals, humans, and the environment.

The ongoing gifts from our generous members has helped us achieve great milestones along the path to animal liberation.

Our Mission

To defend animals, humans and the environment from abuses and exploitation, and to foster peace between all life. We advocate for changes in laws, human behavior, and enlightenment in the need to protect lives, advance rights, improve welfare, and steward environmental protection.

Our Vision

We adopt a worldview that honors the rights and interests of all animals, human and nonhuman alike, as reflected by and achieved through our unique combination of  legislative initiatives, public pressure and awareness campaigns, cruelty investigations, activist support, and direct rescue of vulnerable animals worldwide.

While our perspective and ultimate goals are revolutionary, we recognize and respect the essential role that incremental change simultaneously plays in helping to alleviate animal suffering in the here and now.

"As a youngster, my life saving work focused on rescuing abandoned or lost dogs on the beaches and sand dunes of Long Island, NY."

Elliot Katz, DVM

In Defense of Animals Founder and President Emeritus

"Before persuading anyone else or trying to change a social movement, activists must develop skills of self-understanding, self-acceptance, and self-compassion."

Marilyn Kroplick, MD

President In Defense of Animals