My ex, Sharon, who's also my best friend, has a 15 year old Lab mix and is facing the possibility of having her put to sleep. She has raised Nabs from a pup and they have been constant companions through good times and some pretty bad ones. The dog is now partially blind, and has trouble getting on her feet sometimes but is not in any pain nor is she sick. She does pant a lot with very little exercise. She recognizes people just fine and wags her tail in greeting. She's got a tumor on one of her back legs that is getting bigger, not causing any pain but interfering a lot with her mobility. I've had to have a few of my pets euthanized over the years, but they all had severe short-term illnesses, were suffering a lot and not likely to get better. This is not the case with Nabs--she's not likely to get better but does not appear to be suffering though her quality of life is obviously not what it should be. Sharon is very concerned about the fast growing tumor, and is considering having it removed which a vet has told her might be very difficult if not impossible. The operation, even if it's possible may be very expensive and not buy Nabs much more time anyway even if she does survive it. I tend to think that euthanization can wait until Nabs is obviously suffering, but since dogs can't talk there's no way of really knowing whether that's already the case. Sharon will be a wreck when she does have to let go, but is already a wreck worrying over what's the right thing to do now. Has anyone had an animal euthanized when it wasn't in lots of obvious pain or suffering, but had a significantly diminished quality of life? At what point do you let go?