It worked where I live! 2 seasons of my time and 5,000 rounds of .22s on a close-out-sale for only $15 extirpated them from my area for nearly 9 years now. Not seen nor heard even ONE cat for miles around since every last cat was shot dead and safely disposed of. (You MUST destroy all stray collared cats too, they are the very source of their invasive-species vermin cat infestations. If you don't kill them too then you have done NOTHING to solve the problem.) Before there were hundreds and hundreds of these community-vermin cats torturing to death all the native wildlife on my lands. Today, and for the last 9 YEARS, there are NONE. So much for their oft-spewed "vacuum effect" too, eh? ALL problems solved at the exorbitant price of 1/3rd-CENT per cat, 3 cats per penny -- PERMANENTLY. I dare anyone else to report a more cost-effective, more humane, and more permanent solution than that! :-)