After initially installing the base in your car you can then leave it in place. We got it as we were told our seatbelts weren't long enough to go around a car seat without having to tip the seat forward a little. However, you have to tip the seat forward somewhat to dock it into the base anyway. Also, the seat needs to be pushed down fairly firmly to get it to lock on properly, causing a fair old jolt. So if you are thinking of getting the base so that you can get baby in and out of the car without disturbing them, then think again, the jolt wakes them up. It is fairly easy to use however, and is definitely quicker to dock the chair on this than to secure the car seat with a seat belt (although this is simple to do and only takes a couple of minutes). We've been using it for 12 weeks now and it does make life easier getting the seat in and out of the car, but you could definitely live without it.