This has been an interesting thread. Thanks to all who contributed. I am a beginner, and in my life I think I might have used cue bids once. My impression was that cue bids generally show control. So, if I open 1S, partner responds 2S, and I realize slam is a possibility, on the given hand I might have bid 3D (had I remembered that cue bids exist). That would have said two things: I can't control clubs, and I can control diamonds. I have never before heard of using a cue bid to ask if partner can help with a suit, as earlier responders have recommended. When does a cue bid show weakness in a suit, and when does it show strength in a suit? Thanks very much! RobR