Roman Key Card Blackwood (RKCB)
- After a trump suit is agreed, the asker bids 4NT (RKCB). This is artificial and forcing. It asks partner the number of “key cards” they hold.
- “Key cards” include 4 Aces and the King of trumps.
- The responder bids:
- 5C: 0 or 3 key cards.
- 5D: 1 or 4 key cards.
- 5H: 2 or 5 key cards, without King of trumps.
- 5S: 2 or 5 key cards, with King of trumps.
- After hearing partner’s response, the asker can rebid 5NT to ask for Kings
- The responder bid their “cheapest” king below the trump suit on the six level (or bid the trump suit if no king below the trump suit)