I think that NanRos has a very good point about letting everyone know what is expected of them before they leave the house or go on a play date. It's a good reminder and a clear message. Another suggestion I would make, would be for them to practice the behavior you would like and expect from them; shaking hands, looking at people in the eyes while they speak, saying "thank you", good manners while out to dinner, etc. May sound a little goofy, but it works like a charm for us.
My DS7 is a lemons into lemonade kind of kid, so it can be challenging to find a "punishment" that works. Sometimes we have to resort to taking away books (which is the last thing I really want to do). I find it is more helpful to to catch him before he gets into trouble and to be extremely consistent with him.
Hope this was somewhat helpful. Hang in there!!!
