I have a pretty crazy 2-year old North American mutt who was having trouble with several things - chasing the cat, running off when not on leash and exploding at the front door when visitors came. We tried spray water bottles, time outs, treats, but nothing worked. With this spray collar we have been successful at curbing everything so far. The key is to follow the instructions to the letter. At this point, my dog doesn't associate the collar with me, and doesn't associate the collar with the spray corrections. This way, he follows my commands, even WITHOUT THE COLLAR. This is worth the price, that I was admittedly concerned about. It is imperative to break the dog in by wearing it first, unloaded, for several days, and not making a big deal of it. Then, be SURE that you stay out of the dog's sight when working with the collar - loading batteries, refilling the citronella, turning the power on, etc. Also make sure you wait the full 20 minutes after putting on the collar before you use the spray for a correction. It takes some planning and a little extra effort up front, but it's been worth it. After 2 sprays, I now have control off leash - just give the warning command, and he comes right back (be sure to stay within the 250 remote range continually while outside the first few times). Amazing! Same with the cat and the door. I agree with the other reviewer about the newer, waterproof version, and turning off the collar when not focused on training. We also took on one transgression at a time. Our dog is pretty sensitive, so we started with running away off leash. Then, when we conquered that, we took a few days off, then started with the cat chasing, etc. One last tip, be careful when carrying the remote around that you don't accidentally set off the spray. I accidentally rolled on the remote while I was on the couch watching TV. My dog was asleep when he got sprayed, and was totally freaked out for the rest of the night. We took several days off after that, and he seemed to recover. Best of luck!