agree with you there morloth, on the never make a threat and not follow through, they will soon learn to play you if you do that.
we have the look and the tone of voice in our house the boys know when they have overstepped the line and they will have time out and other consequences such as removal of toys, treats etc if necessary. they also get the 'talk' so they know we are disappointed with their behaviour.
interestingly at my ds's school which the elder three attend they have a red card scheme like football cards, that works well and ds2's teacher also has two lists on her white board, one on one side for the 'naughty' children and one on the other for those who have made 'right choices' it works VERY well, esp for ds2 who can be a handful, he KNOWS i will check everyday if he is on the naughty list and talk to his teacher etc and that there will be consequences to his behaviour at school. his teacher is pleased that i talk to her and back her up if he has been cheeky, or generally just a bit too boisterous etc, she knows she can say to him that if he continues acting out that she will talk to me at the end of the day and there will be consequences and it does make him behave.
i am not talking about smaking him etc, dont do that, but he knows that he will loose time on his ds, or miss out on an after school club etc, they do need boundaries.
i am not overly strict at all, with four boys my house is loud, busy and boisterous, i allow for boys to be boys, but they must know how to behave, especially in school and have respect for people etc ie ds2 was cheeky to a dinner lady, i heard about it via his teacher, he was punished at school, missed some of breaktime but i also made him write a letter of apology at home to take and give to the dinner lady, i think that is only right