Dogs don't understand why they've been placed in to kennels - or whether they'll ever come out again.
But, heartbreakingly, they learn nobody wants them after watching people pass their cage without giving them a second look.
A dog unknowingly saved her own and her shelter mate's life thanks to a heartwarming gesture in the hours leading up to their scheduled euthanasia.
Crossbreed Kala embraced her "shelter sister" Keira, a black and white boxer mix, in a warm cuddle just three hours before their time on Earth ran out.
The duo ended up being rescued by Angels Among Us Pet Rescue, a non-profit charity dedicated to saving dogs and cats from high-risk situations in Georgia, America.
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A spokeswoman said: "Kala and Keira were hours away from their scheduled death on a hot day when a shelter volunteer snapped a photo of them in their kennel and caught a heartwrenching embrace.
"Angels Among Us Pet Rescue knew that immediate action was needed to save these two friends and they pulled them from their dire shelter situation without a minute to spare.
"Kala and Keira's hug and plea for rescue was seen around the world and brought the plight of shelter dogs to the forefront of national and international media and spurred conversations across the globe."
Thanks to their 11th hour plea for help, Kala and Keira were adopted by lifelong friends Wendy and Pam, who spotted their heartbreaking story in a magazine.
Wendy told Angels Among Us Pet Rescue: "I picked up the People magazine after following the story on the hugging dogs, and knew I just had to call."
Wendy had recently lost her two elderly dogs when she saw Kala and Kira's story and realised the "hugging pups" were still available for adoption.
She added: "It just fell together. We turned out tears in to smiles with these two young, playful dogs."
The spokeswoman added: "Kala, 11-month-old, and Keira, 15-months-old, have finally found their permanent home.
"They are happily playing together with Kala following and hugging her best friend, Keira.
"In fact, Wendy says they are working on a special Facebook Page that will keep folks engaged with 'Hugging Dogs' and hopefully raise additional money to help Angels Rescue save other dogs in Georgia’s high kill shelters.
"There are an estimated 2.7 million shelter dogs euthanized every year. For over 60 per cent of dogs, being taken to the shelter is a death sentence.
"At Angels Among Us Pet Rescue, we know that it takes all of us speaking out for those most in need. Our motto is 'Rescue One Until There Are None'.
"We won't stop until every dog is wanted and loved.
"Kala and Keira have shown us that while rescue is hard work and there will be highs and lows as we fight to save them all, sometimes something as simple as a hug makes all the difference."
Do you have a dog story to share? Email paige.freshwater@reachplc.com.
