Both of my boys are indoor only. Allen was an indoor/outdoor cat for the first 10 weeks of his life, and it was just as hard teaching him not to go out as it was Pouncer. They both just wanted OUT. They darted for the door the moment it was opened. You'll learn to get really good at elaving the house while looking for a cat! But eventually they realize just how good they have it inside and have no intense need to go outside.