Hi! I've adopted a few puppies in my lifetime. Some as young as 5 weeks and some as old as 8 weeks. It depends on whether the Mother dog is still feeding the pups. Our last pup Marley was only 5 weeks old as her mother stopped feeding her and her littermates. Just last week I adopted an 8 week old male lab cross. He is doing just great? Hope this helps, Lorraine from Toronto, Canada.