Crrently selected movieclip : how to?

crrently selected movieclip : how to? hi,

I have 3 movieclips as windows on my stage. I would like to navigate between them to attach objects to those 3 movieclips. My question is: How can I tell flash which is a currently selected movieclip…? so that the to be attached object goes and sits in the currently selected widow/movieclip?

Please help…bit urgent pl…