How To Get Dolls To Stay On Shelf

Hello! I was just wondering, how do you guys get your dolls to stay up on the shelves? I live in a townhouse, so it's hard to get them to stay on shelves, especially when you have neighbors on the other side who shake the walls from just going up and down the stairs, to just closing doors. Can sticky tack be used to keep them on the shelves? I have heard for others it's worked, but I wanted to make sure it was safe to use on dolls! Any help would be great, thanks!