Remembering where you put traps is important and they don’t discriminate. Let me clarify something. I would hesitate to put them outside for alarms as it would be hard to hear but placed under a window inside or by a door before bed time would alert you to an intruder. Of course depending on the age of the people or pets in your group this may not be an option. The traps can be rigged out of reach as well. Example would be rigging a string and weight to the top of a window or door using a hook so when the window or door is opened it drops a weight on the trigger plate of the trap that is put up out of reach setting it off. The trap would do no harm but the jaws slamming shut would definitely let you know someone was in the house no matter how quietly they open the door.