After Finn exhibited signs of severe stress on a recent weekend away (and I declined the vet's suggestion to put him on prozac since he seemed to return to normal once at home), the vet suggested I try the Adaptil collar. He said he had seen great results with some dogs but not others. Since I was having house guests over the holidays (which can also stress my silly boy) I figured we'd try it. The collar emits a pheromone similar to a lactating mother dog. It's suggested for new puppies and older dogs with separation anxiety, thunderstorm anxiety, or generalized anxiety. I was pretty skeptical, but figured I was only wasting $20. Well, I have to say, I was surprised. My velcro dog was completely happy and relaxed with our house guests from the moment they arrived. Several times, I noticed my shadow was gone, and I found him happily playing with his toys in another room (that has never happened) or curled up on my DIL's lap watching tv. This may not sound like much, but it's huge. Despite my warnings, my son came into my bedroom after I had gone to bed - and Finn, laying at the foot of the bed just wagged his tail -- no barking. Overall, he seemed more relaxed. My only complaint is that the collar says it lasts 30 days but after 2 1/2 weeks it seems to be wearing off. This may be because the collar got wet during 10 days of rain when I forgot to take it off. Just thought I'd share. Has anyone else used the Adaptil calming collar?