The multiplicity of terminology existed until a few years ago on the therapeutic use of the animals and its implications, caused confusion to the experts and made it imperative to define fixed concepts, common and widely accepted. Undoubtedly, any patient's approach from an animal to a hospital or clinic is not included in the treatment if certain basic conditions are not met (Kruger and Serpell, 2010). The "Delta Society", one of the largest organizations in the United States, which is responsible for the organization and provision of animal assisted programs, has adopted the following definitions regarding the inclusion of animals in the therapeutic context