Outcomes research (OR) is an emerging discipline in animal health care that aims to optimize the results of veterinary interventions. It considers both the clinical impact and economic factors. Economic analyses have been widely used to support decisions in livestock. Although costs remain a crucial aspect in animals intended for food production, animal well-being, a core area of OR, is also becoming more important in livestock. In pets and horses, quality of life is a critical decision factor. However, in these animals, limitations exist to express changes in quality of life or life expectancy in monetary units. This limitation hinders the adoption of economic analyses conventionally used in livestock. Cost-effectiveness analyses have the potential to fill this gap, as they assess costs and outcomes separately. They can support difficult decisions when costs and the well-being of the animal must be considered. Tools have been developed that allow the consideration of quality of life or animal welfare in health economic studies. On a global level, OR can support far-reaching projects, such as disease eradication programs and zoonosis control in developing countries, by evaluating the broad impact of interventions on both animals and humans.