Well said McGrath, to make an evening go well it is better that the song flow from one person to another. To do that you have to have a good selection in your head, and that is what I am aiming to. But I like singing harmony too, and to do that the others have to know the song and the repertoire is likely to be limited. So this is my current dilemma. Is it ettiquette to join anothers persons song if you know it and can do a harmony?

To agree with other posts I have pop song still from my youth, but peoples names are often difficult - strange thing memory isn't it?