I just had to go through a very uncomfortable and unpleasant experience. That of uninviting a player from my group.
This is an experience I wish on no-one, and mostly because I have experienced in from the other side of the table. Of course I write this from my point of view, but I can imagine how the other party feels.
We are social animals, and social exclusion is a very serious weapon if used the wrong way, and not something I would ever, ever do lightly.
I did turn to the web for advice on how best to manage this, and there is not much to be found, but I did find this blog entry on the subject. Though there really is no formula to use for this kind of thing, as each individual case is different.
Have any of you had experience of this from either side of the GM screen? If so, I'd love to hear about it.