Prior to 1986, legislation regulating the protection of animals used in research varied among nations comprising the European Union. In 1986, the Council of the European Communities issued Council Directive 86/609/EEC. The purpose of this directive was to eliminate the disparities in laboratory animal protection laws among member nations. The directive outlines principles such as reduction in the number of animals used in research; guidelines for the adequate care of animals; elimination of unnecessary pain, suffering, distress or lasting harm; and avoidance of unnecessary duplication of experiments. While the provisions of the directive are specific, it is left to each member nation to determine how these provisions will be enacted and enforced. The directive also provided that each nation must comply with the directive by 1989 and that every 3 years each member nation must submit a report on the number of animals used in research.
The major piece of legislation that regulates the use of animals in research in the United Kingdom is the Animals (Scientific Procedures) Act 1986. This act (also known as ASPA) provides for the licensing of experimental and other scientific procedures carried out on any vertebrate animal that may cause pain, suffering, distress, or lasting harm. This act covers all scientific procedures on any vertebrate animal from a simple blood draw to major surgery. While this act was passed in 1986, it continues to be amended to keep pace with changing attitudes and knowledge regarding animal care and use. In 1998, it was amended to more closely conform to Council Directive 86/609/EEC.