Inside the world of homeless, unwanted shelter pets lies an even more desperate class of companions – the hard-to-adopt. If you're a member of this group, you live in the shadows of the shelter, often barely noticed by the visitors who hurry by your kennel each day, looking instead for a younger, healthier, cuter or better adjusted pet. Find out who makes up the group of less desirable animals at shelters across the U.S., and what’s being done to help them find homes.