Adoption dogs. Most dogs in a shelter are dogs that have been given up by their former owner. This can happen for many reasons. Sometimes it happes because the owner suddenly became ill or died. Also changes in the living environment or a change in the family situation can be a reason to bring a dog to a shelter. More dogs end up in a dog shelter than you would think. Adopting a dog is rewarding, you get a lot of love and attention in return.