Evolution and domestication have brought dogs very close to humans. Research has found numerous behavioral, cognitive, neurological, and physiological similarities between the two species. Additional research has found that humans and dogs can share cross-species attachments that are comparable to mother-infant attachments. Furthermore, attachment styles in dogs are classified the same way they are in children. The statistics on the vast amount of dogs in animal shelters, too many of which are being senselessly killed, are shocking. I propose a two-part study that first assesses which attachment style pairings are most successful and which are unsuccessful based on measurements of satisfaction and oxytocin levels reflecting attachment. The second study is designed to verify these pairings by manipulating adoptions and following pairs. If particular pairings are found more successful than others and are utilized at adoption, I hypothesize an attachment style based program would produce more successful adoptions, lower the amount of dogs returned to shelters, and eventually, lower euthanization rates