We bought a side rail for our DS when we moved him into a bed and he hated it, it was like he felt locked in... so we took it away. He has only fallen out of bed once and we put him straight back in and he went back to sleep. Mind you we put DS into a bed when he was 16 months (and that was way too early for him) but we wanted him to be in there for when DS#2 came along - that's a whole other story to tell..... Good Luck xxoo