Roman Key Card Blackwood

There are two versions of RKC: 0314 and 1430 ("Fourteen-Thirty"), which refer to the step responses below.

Playing 0314

Responder's Bids	Meaning
5	0 or 3 key cards.
5	1 or 4 key cards.
5	2 or 5 key cards without the queen of trumps.
5	2 or 5 key cards with the queen of trumps.

Playing 1430

Responder's Bids	Meaning
5	1 or 4 key cards.
5	0 or 3 key cards.
5	2 or 5 key cards without the queen of trumps.
5	2 or 5 key cards with the queen of trumps.

The 4NT bidder can usually (!) determine if responder has 0/3, 1/4, or 2/5 key cards.

Void-showing responses

If responder has a void, she can make one of the following bids to describe her hand.

Responder's Bids	Meaning
5NT	An even # of key cards and a void somewhere.
6	An odd # of key cards and: A club void if clubs aren't trumps, or A void in any other suit if clubs are trumps
6	An odd # of key cards and: A diamond void if hearts or spades are trumps, or A void in hearts or spades, if diamonds are trumps
6	An odd # of key cards and: A heart void if spades are trumps, or A spade void if hearts are trumps

A 5NT rebid asks partner for kings. It is a grand slam try, and should only be bid if the partnership holds all 5 key cards and the queen of trumps.

There are two ways to play 5NT:

1. To ask partner to bid his cheapest (non-trump) king.

2. To ask partner how many kings he holds (standard Blackwood responses):
   • 6 shows 0 kings.
     
   • 6 shows 1 king.
     
   • 6 shows 2 kings.
     
   • 6 shows 3 kings.
     

An example auction playing RKCB with the 5NT "cheapest" king-ask:

			Opener			Responder
			K			A65
			AQT754			K632
			A5			K6
			AQ54			J932
			Opener     1 4NT (1) 5NT (3) 6 (5)			Responder     3 5 (2) 6 (4)

1. RKCB for hearts.
2. 2 key cards without the Q.
3. Asking for partner's cheapest king.
4. Showing the K.
5. Signing off because of the missing K.

Sometimes the 4NT bidder wants to know the location of the trump queen, but hears a 5 or 5 reply. These responses don't indicate whether responder holds the queen of trumps. So, the 4NT bidder can bid the cheapest non-trump suit to ask this question. The responses to the queen-ask are as follows.

An example auction playing RKCB 1430 with a queen-ask:

			Opener			Responder
			AJT75			K93
			AKT			Q3
			AKT2			J8
			5			KQ7642
			Opener     1 3 4NT (1) 5 (3) Pass			Responder     2 3 5 (2) 5 (4)

1. RKCB for spades.
2. 1 key card.
3. Asking for the Q.
4. Denies the Q.

American expert Marty Bergen says that he asked 60 top pairs which Blackwood variant they use. 8 use plain Blackwood, 8 use RKC 0314, and an overwhelming 44 use RKC 1430. ¹

Why is this? Eddie Kantar, author of "Roman Keycard Blackwood: The Final Word", theorizes that RKCB is usually used when a "strong" hand is interested in slam, and wants to ask the "weak" hand for key cards. As a corollary:

"One of the beauties of using Roman Key Card Blackwood instead of regular Blackwood is that it allows the 4NT bidder to ask partner whether he holds the queen of the agreed suit, as well as for other goodies. (Ed. note: See 'Asking for the Trump Queen', above.) To do this economically the asker needs room. The optimal response to 4NT, therefore, is 5 (as opposed to 5) allowing a follow-up bid of 5 to become the queen-ask.

"Playing 0314, a 5 response shows zero or three. '3' is a highly unlikely response when the stronger hand asks the weaker hand, so the 5 response figures to show "0".

"After a zero response the asker usually signs off. The end result is that a 5 response seldom leads to any further asks.

"Playing 1430 the 5 response shows one or four. It doesn't take a rocket scientist to work out that it shows '1'. Now if the asker wishes to ask for the queen, 5 is available. This lower step is especially important when hearts is the agreed suit. Now the queen-ask can be made beneath the five level of the agreed suit.

"Playing 0314, the '1' response is 5, preempting the asker out of a lower-level queen-ask if hearts is the agreed suit. Clearly 1430 works best when the strong hand asks the weak hand."²

Responses when the opponents double

Modified ROPI can be used when the opponents double 4NT. Playing regular Blackwood, ROPI would normally mean Redouble = 0 aces and Pass = 1 ace. Playing RKCB, however, the following scheme saves a little bidding space:

• Redouble = 0, 3 or 5 keycards
• Pass = 1 or 4 keycards
• 5 = 2 keycards without the queen
• 5 = 2 keycards with the queen

For congruity, the meanings of Redouble and Pass can be switched if playing 1430.

Responses when the opponents overcall

There are a couple ways to make RKCB responses when the opponents bid over 4NT. The first is modified DOPI. DOPI normally means Double = 0 aces, and Pass = 1 ace. But when playing RKCB:

• Double = 0, 3 or 5 keycards
• Pass = 1 or 4 keycards
• Cheapest suit = 2 keycards without the queen
• Second-cheapest suit = 2 keycards with the queen

Again, the meanings of Double and Pass can be flipped if playing 1430. Note that DOPI and ROPI are identical in nature, which make them easier to remember than the following method.

Approach #2 to showing key cards is DEPO, which stands for "Double = Even number of key cards, Pass = Odd number of key cards." Thus:

• Double = 0, 2 or 4 key cards
• Pass = 1, 3 or 5 key cards

The benefit of DEPO is that it's more economical over high-level overcalls such as 5 or 5. You can always stop at the 5-level, which is not guaranteed if playing DOPI.

• It is important to agree with partner when RKC is on, and when it is off. Sometimes one player wants to just ask his partner how many real aces he holds, and this can cause a lot of confusion at a precariously high bidding level.

• In short, RKCB can get very complicated. That is why Kantar was able to write a 244-page book about it. It requires a healthy amount of partnership discussion.

Roman Key Card Blackwood was initially based on Roman Blackwood, a Blackwood variant that was used by the famous Italian Blue Team in the 1960s. American expert Eddie Kantar is credited with popularizing the "key card" nature of the convention thereafter.

¹ Bergen, Marty (2008). Slam Bidding Made Easier. Note: Mention "BRIDGEBUM" when buying this book directly from Marty to get 2 softcover books free.

² Kantar, Eddie (2003). "A Key Question". ACBL Bulletin, January 2003.