The 3Rs framework - Replace, Reduce, Refine - guides laboratory animal welfare improvement. Refinement advances that reduce suffering without eliminating animal use represent immediate welfare gains.
Refinement represents the most immediately applicable component of the 3Rs framework, improving welfare for animals that remain in laboratory use regardless of parallel progress on replacement. Evidence-based refinement - applying documented improvements like tunnel handling, enriched housing, and appropriate humane endpoints - can substantially reduce the suffering of laboratory animals without reducing scientific utility. Institutional adoption of refinement advances requires researcher training, institutional culture change, and regulatory frameworks that mandate rather than merely recommend best practice.