Replacement - Reduction - Refinement
Russell & Burch launched the idea of the 3Rs in their book The Principles of Humane Experimental Technique in 1959. It was not until the 1970s that the interest in this book and the 3Rs started to grow. The 3Rs have now become world famous and are the central focus of laboratory animal science today.
Replacement refers to scientific research in which live animals are no longer necessary, including computer simulation models. Reduction refers to reducing the numbers of animals necessary in scientific research, for example through the application of improved statistical techniques. Refinement covers not only improvements in experimental techniques, but also improvements in animal welfare – environmental enrichment is a good example of this. It is the challenge of today's laboratory animal scientists to research, implement and fully integrate the 3Rs effectively into medical and biomedical research.