Animals used in research have contributed mightily to the advancement of human health. There have also been egregious uses of animals in pain, physiological, and psychological studies; cos- metic testing; and teaching programs. Some animal models have provided little information for treating disorders in humans, and research results from animals housed in facilities that fail to reflect natural environments (and variables) often yield results that cannot be translated to other species or environments. This review provides a historical overview of the use of animals in re- search, describes some of the limitations associated with the current medical research model, and proposes a new model that provides opportunities for breakthrough discoveries with a higher probability of preventing disease and developing gentler therapies for both animals and people.