SLAM Bidding

   

The meaning of a 4NT bid and the following bidding style depend entirely on the on CONTEXT of the 4NT bid.

1. Quantitative 4NT

A.  A direct Jump to 4NT from a NT bid in any of the following balanced sequences (and no other):
(i) 1NT(opening) -  4NT
(ii) 2NT(Opening) -  4NT
(iii) 2-2X-2NT - 4NT
(iv) 2-2NT-3NT-4NT

Note: Following a 2 & opening 4NT Quantitative never applies
 
Valid responses are:

PASS  (not allowed for (iv) )   No interest in SLAM
6NT                                                 Accepted - no interest in a grand slam
ERKCB responses   <= 5NT         Showing interest in a SLAM and top honours

2. 2 Sequences

4NT following a 2 opening and any Positive response, is ALWAYS for Kings:
This bid should normally only be made by the 2 bidder. Occasionally if the NT bidder makes a control request, the response to which would reach or pass 4NT then see this special case given below: '4NT by responder'.

Responses are:

5:      0 Kings
5:      1 King
5:      2 Kings
5:       3 or 4 Kings

A positive response to 2C shows 1 or more controls (K=1;A=2)

With this response the 2 bidder therefore unravels the Number of Aces simultaneously.

Following this a 5NT request for other key honours, responses are:
6:       No Queen of trumps
6:       Queen of trumps
6:       Queen of trumps with either the J of trumps or another useful queen
Responses should not bypass the agreed suit.

When the initial response to 2 is a negative (2 or 2NT which denies Kings or Aces); 4NT will ask for Queens with the three above responses given at the 5 level.

When responder bids 4NT or passes it:

Then bidding 4NT shows 2 or 4 Kings. Presumably previous responses can unravel this.
Then passing above 4NT shows 1 or 3 Kings. Again, presumably previous responses can unravel this.
(in fact a modified TURBO)

2 bidder may continue with 5NT as above or proceed to the agreed suit.

3. Cue Bidding and TURBO 4NT

Turbo is automatic in these cases:
Bidding 4NT shows an EVEN number (2 or 4) of KeyCards(KC) while bypassing 4NT declares an ODD number of KC (1 or 3).
Key Cards are the 4 Aces and K of trumps as in RKCB.

When a major suit is agreed below 3NT and either player bids 3NT, without using trial bids), then this shows an EVEN number of KC and a 4-level bid bypassing 3NT will show an ODD number as above.

There is another aspect to TURBO for indicating the Queen of trumps:
Partner needs to be aware that in these sequences bidding game is only a warning about the Queen of trumps and partner should NOT treat it as a stop bid if a slam is in the offing.

4. 4NT with a jump is ERKCB

(That is when it is not Quantitative or if 2C was the opening bid. Also not if cue-bidding followed agreement)
The trump suit is  either already explicitly known otherwise implicitly now defined as the suit bid just prior to the 4NT bid.

See ERKCB responses.

In some ERKCB sequences there may be 6 KEY cards (i.e. that is additional key kings) Valid kings in known suits of the 4NT bidder.

Sequences for 6KC:
A)  1X - JY and subsequent trump support shown for either X or Y.
In this cases 4NT bidder must possess a minimum of 2KC

A rebid of 5NT following a 4NT EKCB shows all 5 Key cards are held and is a Grand Slam try..
If the existence of the agreed trump suit has not been located, then, the primary response to a 5NT bid is to seek the Queen.
Responder bids 6 of the agreed suit without the queen, and the suit of any hithertoo undeclared K.
If the queen is discovered, then,  5NT is seeking further information. Again if nothing useful is  around the idding closes in 6 of the agreed suit, otherwise the responder bids location of the feature e.g.  A void,  a useful side K not inferred in previous bidding.

5. Following special 3C/D 2-suited sequences

Responses show a conservative LTC where K are not counted  unless supported by the Ace,  A King supported by a Queen may be counted, however the Queen cannot be counted. Singletons without the Ace & Voids are counted as  1 & 0 LTC counts in their suits.
5C:   8LTC; 5D: 7LTC; 5H:6LTC; 5S:5LTC;5N: 4LTC  This may occur if preference is not given to opening 2C (Typically opening 2C is  valid if one suit has a lower LTC than the other. Stronger 2-suited sequences are not able to indicate which suit is superior.