Thought I'd add a few links on the topic: http://www.wenet.com/~amazon/happycat.html http://www.vospca.org/archive/indoorcat.html http://www.runway.net/b/moonmaid/in-or-out.html http://www.hdw-inc.com/leashtraining.HTM http://maxshouse.com/Healthy+Happy_Indoors.htm