when my eldest was two she thought is was amusing to get a reaction out of us by putting her finger in the elctric sockets, third time she got a smack, which im sure was less harmful than an electric shock. i dont like smacking, but sometimes the short sharp shock is necessary just to create a 'full stop' to whatever misdemeanour is going on. Having said that it doesnt need to be hard and 99% of the time a loud 'oi' will get the childs attention...then have you follow it up with the rational bit coz a smack on it's own says nothing constructive. When smacking came up in the news last time, there seemed to be a notion that a child should only be smacked after a certain age, ( i think 7) and that i had to disagree with, 7 year olds and older are rational and can be dealt with in better ways, a smack is just pain and humiliation to them, but an 2 year old often isn't even listening let alone understanding, that's the only stage where i think a smack can be helpful.