Successful implementation of refinement requires consideration of the entire lifetime experience of the animal, not just the animal's experience during an experiment.

Animals used in science are obtained from a variety of sources including: agricultural organizations, commercial breeders, in-house breeding programs, the wild, and animal shelters (however, not all provinces permit acquisition from animal shelters). Factors related to the procurement of animals, such as animal supply and transportation, influence the implementation of reduction and refinement.