We have three cats, two of whom go outside. Number three is very old and creaky, and now prefers the sofa.

None of our cats hunt -- as ex-strays, I imagine they've been there and done that -- and typically they stay out for, at most, an hour at a time. During the summer, that time is spent under the leaves of the hosta or rhubarb plants in the garden; in the winter, it's a quick dash around the perimeter and then back in. The big, domineering tom goes out to check on incursions into his territory; if we're slow opening the door he pisses on it. The little old female goes out to establish that the outside is still there.

This system works well because we live in a quiet enclave, and because they go out only when we are at home and awake; we call them in before going to bed or leaving the house. Yes, they come when we call; it's not hard to train a cat if you make it worth his while.