Control Cue Bids

These are bids that show controls (aces/voids and kings/singletons) in the bid suits, usually used in slam explorations. The first time a suit is cue bid, it shows a first round control (Ace/void). The second time a suit is bid, a second round control (King/singleton) is shown.
If partner cue bids to show a 1st round control, and responder lacks any, responder rebids the agreed-upon suit. If the partner continues to cue bids, s/he tends to show 2nd round controls. Responder's subsequent bids therefore also are 2nd round controls.

             S: x
             H: Jx
             D: KJxx
             C: KQxxx

             S: AKx
             H: AKQxxx
             D: x
             C: Axx

W        N       E        S

P        2C      P        2H
P        3H      P        4C
P        4H      P        4S
P        5C      P        5D 
P        6H      P/O