Great Britain has been a world leader in animal research since 1876, when the country passed the world's first law regulating animal experimentation. The Cruelty to Animals Act has been revised multiple times over the years. In 2009, an all-out ban on animal cosmetic testing will be enacted throughout the European Union. This will include both the testing of products on animals, and the sale of products that were tested on animals. Britain still requires all medicines to be successfully tested on two different species of animals before sale. Over 2.5 million animals are used during research in the UK each year, including over 23 thousand rabbits and 1.6 million mice. The amount of animals being used in the country has been halved since 1960.

The first legislation covering animal experimentation in the United States was the 1966 Animal Welfare Act. It has been amended five times since then, the last time being in 1991. The 1985 amendment established the use of committees to review the use of warm-blooded animals in research. These committees are called Institutional Animal Care and Use Committees (IACUC). Each consists of at least 5 members: one being a veterinarian, one a research scientist, someone not affiliated with the research institute in any way (except through this committee), and someone whose main concerns are not involved in science. One of these committees is required for every research institute in the country. While there are complaints about the use of these committees, many scientists admit that their usage has improved both the lives of research animals and the research resulting from the experiments. In order for an animal experiment to be conducted, a scientist must prove that the experiment has a justified end and has not been performed before. For example, a scientist would likely be denied the ability to test the toxicity of arsenic on animal subjects, as this information is already known. Arsenic is highly poisonous.

Most vivisection opponents are not seeking an immediate halt of the practice. Many look to the "Three R's" for an improvement of animal use in a lab. Coined in 1954, these R's stand for: reduction, refinement, and replacement. They seek to reduce the number of animals used in an experiment to the bare minimum, refine the amount of suffering animal subjects will endure, and replace as many subjects as possible with alternative testing methods, or with less sentient species.