Slam bidding

Things other than blackwood

cuebids

Non-jumping cue bids made after suit agreement are Italian, stating second round (or better) controls in the bid suit and no second round controls in skipped suits. If a suit is skipped, the next bidder must revert to trump unless responder has the skipped suit. In diamonds bid NT to deny clubs (because a reversion to D might be RKC).

splinters

Jumpshifts that are not otherwise conventional are splinters indicating a minimum 9 card fit, a singleton or void, and 10+ support points if points are not already disclosed.

Quantitative 4NT

a bid of 4NT over an agreed NT asks partner to go to 6 with maximum holdings and pass without.

Grand Slam Forcing

A bid of 5NT over a suit is GSF, bid 7 holding 2 of the 3 top honors. Without the responses are suit dependent:

spades

6C - no top honors
6D - Qxx(x)
6H - A/Kxx (exactly 3 trump)
6S - A/Kxxx(x) 4+ trump

hearts

6C - No A/K
6D - A/Kxx
6H - A/Kxx(x)

diamonds

6C - No A/K
6D - A or K

clubs

6C - fewer than 2 top honors

Vol-5

A bid of 5 of an agreed major or a jump to 5 of partner's major asks partner to go to 7 with maximal holdings or 6 without. This should be rare as it is rather imprecise.

Fundamentals

The primary slam finding vehicle used is 1430 Roman Keycard Blackwood (hereafter 1430). It is generally bid at 4NT, but can be at other places so I'm using steps to notate the bids. A step is any bid, including NT or the trump suit, and a keycard is any ace plus the king of trump.

1 step - 1 or 4 keycards
2 steps - 3 or 0 keycards
3 steps - 2 keycards without the queen of trump
4 steps - 2 keycards with the queen of trump

occasionally used is traditional RKC (3014) which is the same as above except the first two steps:

1 step - 3 or 0 keycards
2 steps - 1 or 4 keycards

1430 is used unless one of the following is true (then it's 3014):

rkc responder opened 1c
rkc responder made a strong jumpshift
rkc bidder made a "weak" opening (preempt or weak 2)
rkc bidder has previously passed (should be very, very rare)

over interference

positive responses are optional. Below 6 of the suit 1430:

(re)double - 0 or 4
pass - 1
1 step - 2 
2 steps - 3

3014:

(re)double - 2
pass - 3
1 step - 4

If the interference is above 6 of the suit responses are DEPO (double even, pass odd).

After responses

After the RKC responses the original RKC bidder has three basic options:

raise of 1 step: Queen Ask (only if queen hasn't been shown/denied)
lowest remaining NT: Specific King Ask 
return to trump: to play
any other suit bid: Specific Suit Ask

Queen Ask

After a queen ask the following followup responses are available:

return to trump at lowest level - no queen, no 10 card fit
jump to small slam in agreed suit - queen, nothing else
another suit - queen (or 10 card fit) and king of this suit
nt at lowest level - queen (or 10 card fit), no outside kings, feature

A feature in this case is defined as:

queen of partner's first-bid side suit
third round control in partner's second-bid side suit
extra length in the long trump side
if no side suits were bid, third round control anywhere

Following a NT feature bid a suit bid other than trump asks if the feature is in that suit. Return to trump denies, grand in trump agrees, grand in bid suit (if below trump) shows QJ (looking for that elusive 7NT).

Specific King Ask

Specific King ask guarantees the prescence of the Queen of trump. After an SKA responder bids his lowest king, or returns to the trump suit. Following either a positive SKA response or a king showing response to the queen ask, a bid of another suit by RKC bidder asks for the king in that suit. Responses:

return to trump suit - no king 
1 step - Kxx(x)
2 steps - Kx (or x in trump, second and third round controls)
raise of bid suit - KQ(x)

Specific Suit Ask

Requests information about bid suit. steps include nt, but not trump. If 2 steps passes small slam, remove third round controls from ask list (same as above in later bids to Specific King Ask)

1 step - third round control
2 steps - Kxx(x..)
3 steps - Kx or x(suit only) (second and third round controls)
raise of ask suit - KQ(x)
jump in trump suit - singleton with 3 cards trump support for SSA in 
 an unbid suit or 4 cards trump support in a bid suit.

If ops interfere (steps now count trump, if 2 steps passes trump and wouldn't have previously, return to trump on Kxx or Kx).

(re)double - nothing
pass - third round control
1 - step Kxx
2 - steps Kx 
return to ask suit - KQ(x)
jump in trump suit - unchanged

Exclusion Keycard Blackwood

Exclusion keycard blackwood shows a void and asks for keycards in suits excepting the bid suit. The bid to initiate EKB differs depending on the situation. Responses:

1 step - 0/3
2 steps - 1
3 steps - 2

responses over interference:

(re)double - 0/3
pass - 1
1 step - 2
...

further responses are the same as RKC (queen ask may not be in NT and a bid of the void suit if it is not the queen ask is SSA for whatever suit would have been the queen ask)

One club opens

A one club opener has a few special options open.

Minor RKC

See the non-agreed section on minors.

Strong EKB

A shift to an unbid suit at the 4 level or a jumpshift to any suit not bid by opener at the 4 level is Exclusion with implied agreement to the last bid suit. So 1c-1h-1s-2d-4h is EKB for diamonds with a void in hearts.

Majors

When trump suit is a major RKC is bid with 4NT (either 1430 or 3014, see above). An additional set of responses is available to show voids:

5NT - 2 or 0 (very optional) with a void 
6C, 6D, 6H - 1 or 3 with a void in the bid suit or spades if hearts are bid
and trump

Exclusion Keycard Blackwood in Majors

If unlimited hand wishes to bid RKC excepting a suit (because of a void) bid above game in the void suit. see Exclusion Keycard Blackwood.

Running out of room in hearts

If the response to RKC is 5d then 5h is to play against 0 or 1 keycard and queen asking with 3 or 4 keycards (pass with no queen). Also any bid of a known singleton (for instance a splinter suit) to indicate a specific suit (for instance in response to a king ask or making a suit specific ask) indicates Spades.

two suited hands

If one partner has a two suited hand, count both kings as keycards, responses are unchanged

double agreement

If two suits have been agreed to, count both kings as keycards and replace 3 steps and more with the following:

3 steps - 2 keys, no queen
4 steps - 2 keys, one queen
5 steps - 2 keys, both queens

If 5 steps puts us below 5NT; 4 steps shows the lower queen, 5 the upper, and 6 both.

Non-agreement

after a one major or one diamond opening, if a responder does jumpshift 
 to a major, a non-agreed 4nt by responder insists on the jumpshift major.
after a one major opening followed by a jump rebid or 3 level rebid 
 after a jumpshift, a bid of 4NT by opener insists on his own suit.
after a 1c open, opener bidding 4nt without agreement after showing a suit
 insists on his own suit.
after a 1c open followed by a positive response, 4nt without agreement by
 responder insists his own suit.
all other non-agreed major RKC tries agree to last-bid suit

Minors

Agreed at the three level

In a game forcing sequence or if two or more suits remain unbid, 4 of the agreed minor is RKC. In a non-forcing sequence with one or fewer suits unbid 4D is RKC for clubs and 4H is RKC for diamonds.

Agreed at the four level

A single step (4D from 4C or 4H from 4D) is RKC for four level agreement unless that would shift to a suit named in the first round of bidding. Then you must shift to the lowest suit not mentioned in the first round (or 4NT).

Non-agreed

after a 1c opener followed by a second-bid minor by opener, opener may bid
 4 of his suit to force RKC in his suit
after a 1c opener followed by a positive minor response, either opener or 
 responder may bid 4 of responder's minor to agree and start RKC
after a one major or one diamond opening followed by a minor jumpshift, 
 responder may bid 4 of his suit to force agreement and RKC
after a one diamond opening followed by a jumpshift, responder may bid
 4 of opener's suit to agree and start RKC

In all other situations, to make a non-agreed RKC in a minor the suit must be rebid or a 6 card suit must be indicated, the asker must be unlimited, and bidding must be at the 3 level. The bid is 4d over 3c or 4h over 3d.

Voids

A jumpshift responder may jumpshift to an unbid suit for exclusion, all other bidders must jump to 5 of an unbid suit.

After normal RKC there are responses to show voids:

raise of the ask suit - 0 or 2 keycards with an unknown void
jump - 1 or 3 keycards with a void in the bid suit or the suit below 
       the ask suit if the bid suit is trump

The queen ask remains one step above response (including NT) and all other suits responses (except trump) are SSA.

No Trump

The standard ace asking mechanism after No Trump is Gerber. 4C following an agreed No Trump or immediately following a natural NT bid asks for aces.

Over interference

Below 5S responses over interference when RKC would have been 1430 are DOPI

(re)double - 0 aces
pass - 1
1 step - 2
2 steps - 3

If it would have been a 3014 situation in RKC then responses are modified:

(re)double - 2
pass - 3
1 step - 4

Above 5S it's always DEPO (double even, pass odd).

Credits and Final notes

This page was taken substantially from Eddie Kantar's Roman Keycard Blackwood. It was layed out specifically for my system and though lots of its features would be useful for another system, I would strongly recommend getting the book and reading it if you want to develop an agreement for something more traditional (like, say, 2/1)