Animal Research Ethics — 3Rs Principle

The 3Rs (Replacement, Reduction, Refinement) is the ethical framework governing humane animal research, established by Russell and Burch (1959) and now adopted globally by research institutions, funding agencies, and regulatory bodies. The 3Rs require researchers to: replace animal research with non-animal methods where possible, reduce the number of animals used through rigorous design, and refine experimental procedures to minimize animal suffering. Implementation of the 3Rs is now mandatory in most jurisdictions through Institutional Animal Care and Use Committees (IACUCs), EU Directive 2010/63/EU, and NIH policy.