I live up many flights in the back corner of a building right in the middle of the city, here in DC.... and it is not all that safe to take a little dog outside after dark and we have had some horrendous rain storms in the past year. Riley is trained to use the pads if he really needs to, but will also go, outside. It also makes it convenient when staying with some of my friends who live way way up in some of the taller buildings, in New York.