we let my bro's 8, 6 and 4 year olds outside here to play without adult supervision - provided there is two of them together. we have no fences at the front and back so we tend to limit where they can go - thankfully they're good kids and don't go past the shed unless there are adults with them. we only loosely supervise if we're outside with them to make sure they don't go past the back fence, don't torment the cattle dog (he has to be tied up when he's home cos of no fences unless DH is out there with him - won't come back for me!) or get tangled in his chain. we have a double block though with heaps of space and lots of stuff for them to get into - so it's not something i think i'll be comfortable with until E is much older. i don't hover, i just go about doing my own thing and make sure i can hear what is going on. to do that from inside i'd have to be in my bedroom with the ensuite window open, and if someone got hurt, have to go to the other end of the house then right down the backyard to help them out so it's just more practical to be outside with them...