MINOR OPENING  12–21 hcp (high cards points) 

The rules propose for this opening apply only for non passed hand with an auction without interference. With interference read here.

 RULE-01: After a minor opening (1/1) the following responses bids are transfers for strong hand receive the lead: 4 transfer to 4; 4 transfer to 4; 4 transfer to the other minor not bided. These rare hands with 7/8 cards should be limited up to 10 hcp with only one ace and good suit (up to 1,5 loser).

 RULE-02: After a minor opening (1/1) the response in 4 is Gerber even if with interference in the auction. The Gerber used here has no continuation for asking Kings, so any bid by Responder after the Gerber's response will be conclusive.
When Responder needs to know about the possession of trump's Queen it's necessary first support partner at level 2 (using inverted minors conventions) and after apply the Kantar' RKB schema, so Gerber is only for aces:
Opener Responder         Opener Responder
   1     4 <= Gerber       1       4 <= Gerber
    ?                                   ?
The answers are: 4=zero or 4 aces/ 4=1 ace/ 4=2 aces /4nt=3 aces
After the Gerber Responder's bids in:
4; 4; 5; 5; 6; 6; 6; 6; 6nt; 7x are conclusive.
Some possible hands to use Gerber after minor opening are:
a) x KQJ109xx AKQJ x 
b) AKQJ10xx Kx x KQx
c)  x KQx KQJ109x AKx
d) AKx x KQJ10xxxx x
e)  x KQ10 KQx AKQJxx
f)  x x KQJ10x AKQ10xx
Remeber that: 1 response 4 is transfer to 4 so can't be RKB1430.

 RULE-03: After a minor opening (1/1) the response in jump to level 2 like 2/2 are weak showing 6/7 cards with less than 6 hcp, so Responder may pass after Opener's second bid in other suit or rebiding his own suit, but some possible hands used as weak jump like below can fit with Opener's hand and game can be possible:
a) Qxx QJ10xxx xx xx 
b) K109xxxx x xx Jxx
c) xx A1098765 xx xx
d) x KJ106543 xxx x
e) xx KQ10865xx xxx
f) KJ8732 xx xx Jxx   

RULE-04: After a minor opening (1/1) the directly response in jump to level 3 like 3/3 are splinters GF showing 5 cards support in the opening minor and singleton in the major bidded. These responses has strength limited up to 18 points (3 points for the singleton and up to 15 hcp).
Possible hands to use mini splinters at level 3 after 1 are:
a) x Q10x Kxxx AQzxx  <= 3 splinter (14 points)
b) AJx x Kxx KJ10xxx  <= 3 splinter (15 points)
c)  KQx Kxx x AJ10xxx <= 3 splinter (16 points)
Possible hands to use mini splinters at level 3 after 1 are:
d) x KJx 109x AQxxxx <= 3 splinter (13 points)
e) KQx - AJxxx A9xxx   <= 3 splinter (17 points)

RULE-05: After 1 opening the response 3 means 6+ cards with 8-11 points (each card after the 4th card counts 1 point) and the hand must have honors concentration in Clubs. This is a special need of 2/1 system to be Two Overc One Game Force considering that response 1nt is up to 9-10-hcp and response 2nt is restricted to 11 hcp without singleton or 6+ cards.   

RULE-06: Hands limited up to 15 hcp with distribution 6-5 where the 6 cards suit is low ranking like 6-5 or 6-5 or 6-5 or 6-5 or 6-5 depending on the number of losers - up to 4 - may be opening in the low ranking suit with 6 cards and after reverse bidding the high ranking suit. But the non good suits (more than 4 losers) should be treated as 5-5 hands bidding first high ranking 5 cards suit and then twice the 6 cards suit, if it is possible. Of course hands 6-5 with 16+ hcp should always be bidded in reverse.
example
x KJ865 x AKJxxx opening 1
   and after response 1 second bid is 2 and
   if Responder bids 2/2nt then third bid is 3.
x KJ1098 x AKJ10xx opening 1
   and after response 1 second bid is 2 and
   if Responder bids 2/2nt then third bid is 3.
but when the suits are Spades and a minor weak 6-5 should nor be opened in one Spades like:
 KQ7xx 5 x AKJxxx opening 1
    and after response 1 second bid is 1
    if Responde bids 1nt or 2 then third bid is 2
 AKJxx 6 x AKJxxx opening 1
    if Responder bids 1 then Opener's second bid is 2
    because Opener has 4 or less losers
    so after Responder bids 2nt/3/3 Opener rebids Spades
 AKJxx 6 KQJ10xx x opening 1
    if Responder bids 1 then Opener's second bid is 2
    because Opener has up to 4 losers
Some partership still play like old fashion in jump to 4 level to show a 6-5 hand minor-major with up to 4 losers, but we believe that is more construtive and possible shows these hands in low level as we exemplify above allowing the level 4 to be used in asking for keycards with void in the suit bidded and with strong support in Responder suit. Of course these situations occurs rarely but we should be prepared with a specific bid.
Opener Responder         Opener: KQx KJ103 - AKJ10xx
    1        1               or Opener: - AJ103 Kxx AKQ10xx
  4/4 <=EKB1430 (Exclusion Keycard Blackwood)
           the suit bidded by Opener is a void and any ace should be ignore
           step1 = 1 or 4 keycards            step2 = 0 or 3 keycards
           step3 = 2 keycards without Q   step3 = 2 keycards with Q
 After the Responder answer the bid of 5/6/6 are conclusive
 But the next suit is asking for the Queen and
 another suit is SSA (Specific Suit Ask)  read SSA
++++++++++++++++++++++++++++++++++++++++++++++++++++
1 OPENING - without interference by opponents

 Opener Responder   
  1    ?
           1 => generally 5+ cards and no major
              if Responder has 5+4M then:
              with 12+ hcp Responder bids first 1 and after 1nt/2
              Responde then bids his major in reverse showing 5-4; 
              with 5-11 hcp Responder bids first his major and after 1nt
               Responder may: pass;
               Responder may: bid 2nt invitation with 10-11 hcp;
               Responder may: bid 3 sign-off with 6-4major up to 9 hcp
                   because now the 2 bid is artificial for NMF.
           Note: After response 1 Opener only bids a major with 54M
                    - read Walsh convention.
           1 => 4+ cards 6+ hcp
           1 => 4+ cards 6+ hcp
          1nt => denies major 6-10- hcp and denies 5/5 cards
           2 => 5+ cards and 10+ hcp - read inverted-minors
                      Responde hand with 12+ hcp and distribution 4333
                      or 4432 may support Opener with only 4 cards
                      but with only 10-11 hcp need 5+ cards for inverted
           2 => 6+ cards weak - less than 6 hcp - need one top honor:
                     xx Jxx KJxxxx xx
                     x Jxx QJ10xxxx xx
                     10xx x A109876 Jxx 
           2 => 6+ cards weak - less than 6 hcp - need one top honor:
                     x QJ98xx 987 Jxx/
                     Qx K1098xx 9x Jxx
                     xxx A98xxxx - Jxx  
           2 => 6+ cards weak - less than 6 hcp - need one top honor
                     K98xxx x xxx Jxx 
                     A98xxxx xx xx xx
                     QJ1098xxx x xx Jxx  
         2nt => 11 hcp no majorn no 5+ cards -semi stoppers in majors
                     K108 A10x Q10x Q9xx
                     QJ8 J10x K109 KJxx
                     J98 KQ9 KQ98 109x 
           3 => 5+ cards weak 5-9 hcp - read  inverted-minors
           3 => singleton 5+ cards up to 18 points -GF - denies major
           3 => singleton 5+ cards up to 18 points -GF - denies major
           3 => singleton 5+ cards up to 18 points -GF - denies major
          3nt => balanced 16-17 hcp with 4 in 4333 or 4432
                 KJ8 AQ xK10x K9xx  or  AJ KQ8 QJ10x QJ9x
                 read 1minor-3nt
           4 => Gerber asking for aces (do not imply in Clubs support)
           4 => transfer to 4 7/8 cards no 2 aces up to 10 hcp
                      8 KQJ109xx A7 109x  or   8 AQJ109xx 7 1097x
           4 => transfer to 4 7/8 cards no 2 aces up to 10 hcp
                      AQJ1098x 9 K75 10x  or   KQJ1098xx 9 K7 10x
           4 => transfer to other minor (5) no 2 aces up to 10 hcp
                      10x x AKJ98732 Jx   or   x x KQJ10763 Kxxx
         4nt => RKB1430 for Clubs - afraid interference strong hand
          5 => preemptive 7/8 cards - no aces or void - up to 10 hcp
                     J109 9 K5 KJ10xxxx  or   x K109 x KQJ10xxxx      
 5/5/5 => exclusion RKB1430 for very strong Responder's hand
                       (the suit bidded can't be counted for ace)
 ................ 1step= 1 or 4 keycards; 2step= 0 or 3 keycards;
 ................ 3step= 2 keycards without Q; 4step= 2 keycards with Q.
Opener's second bid after response 1
Opener Responder 
  1      1   
   ?
  1 => shows 54: Jx KQxx Qx AJ98x (Walsh) or 4414
  1 => shows 54: QJxx KQx x AQ98x (in Walsh promise 5+)
              can also have a weak hand 11-14 hcp with 6+5 or 5-5
 1nt => balanced hand - no singleton: QJ8x KQ92 Qx K9x
             (playing Walsh can have both majors in this sequence)
  2 => shows 6+ cards up to 17 hcp : Qx KQx xx AQ98xx
             note: if Clubs is a good suit then with 16-17 hcp jump to 3
  2 => support with honor 3rd or 4 cards: 
             xx KJ8 AJx AJ982  or  x KJ8 Axxx AJ982 
  2 => reverse 16+ HCP with 5+4:  Kx KQ10x Qx AQJ9x
              also may be a 6+5 up to 4 losers: x KJ1098 x AKJ10xx
              After a reverse Responder must use Leb reverse convention
              published at LEBENSOHL CONVENTION where:
              Responder shows a weak hand (5-7 hcp) bidding 2nt
              that is transfer to 3 (bidding 3 establishing GF sequence).
              Responder then can pass in 3 or rebid his suit to sign-off
              Thus, after 2nt Opener with a low reverse 16+-18- hcp bids 3
              but with a high reverse 19-21 hcp don't accept the sign-off
              and bids 3nt or game in a minor suit or bid the 4th suit for GF.
  2 => analogous previous situation
 2ST=> balanced hand with 18-19 hcp, ex: K10x KQ10x Qx AQJ9
             Responder with 5-6 hcp can pass; 
             Responder with 7-12 can sign-off in 3nt;
             Responder with 13+ can search for Diamonds support bidding
               a reverse 3/3 suit with Slam interest.   
  3 => 6+ solid cards with 16-17 hcp (AKQxxx or AKJxxxx)
              Axx  10x  Kx AKQ10xx  or  Kxx x Ax AKJxxxxx
             Responder can: pass; bid 3nt; bid a major stopper to try 3nt
             or just support Opener in 4 to try Slam or just game
  3 => support with 4 cards and 16-17 hcp - almost a GF unless
             Responder has weak 5-7 hcp. Thus, any major bided by in
              sequence is (in principle) a stopper trying 3nt, but can be
              a cuebid with Slam interest if Responder continue after 3nt.
 3/3 => are splinters with 4 cards support and up to 18 points - GF
              Kxx x KQxx AQJ9x  or  x Kxx A109x AKJ9x
              Note: when a fit is found and hand have a singleton we add
              3 points for the singleton having 4 cards support.
              So, points = hcp + distribution values,
 3ST => solid Clubs suit AKQJxx, AKQ10xxx, with stoppers in majors
              Ax  Q10x  x AKQJ9xx  or  Kx Kx x AKJxxxxx
  4 => cuebid in Clubs with 4 support (Kx xx KQxx AKQJ9)
              waiting for cuebid to bid 4nt1430 to try Slam
   4 => RKB1430 for - Opener has strong support for Diamonds GF
  4 => EKB1430 for with void in Opener has strong support for
             Kxx - KJ10x AKJxxx or Ax - QJ109 AK109xxx
             Exclusion Keycard Blackwood responses are: step1 = 1 or 4;
             step2= 0 or 3; step3= 2 without Queen; step4= 2 with Queen.
  4 => EKB1430 for with void in Opener has strong support for
             - Kxx KJ10x AKJxxx or - Axx QJ109 AK109xx  
 4nt => Blackwood for aces - want to know if partner has A not K
             probably strong Clubs hand with singleton Diamonds
  5 =>  to play - no strong hand just long suit 7/8 - up to 15 hcp:
              A8 x Jxx AKJ10xxx  or  x Ax xx KQJ10xxxx    

Opener's second bid after response 1
Opener Responder
   1       1
     ?
   1  => 4+ cards and 12-15 hcp
               but can also have a weak hand with 6+5
   1nt => shows 12-14 hcp and 4/5 cards
   2  => normally 6 cards: Qx x KQxx AK98xx
               but may also have 5 in 1345 distribution
   2  => 5/4 reverse hand 16-21 hcp -
               Responder must use Leb for reverse now
               may have also 6/5 with up to 4 losers not strong in hcp  
   2  => 4 cards support - 12-14 hcp 
   2  => 5/4 reverse hand 16-21 hcp
               Responder must use Leb for reverse now
  2nt => balanced hand 18-19 hcp
              Responder can use New Minor Forcing bidding 3
              Opener with balanced hand and 18-19 hcp having 4 cards
              should not jump to game in 4, because a jump for 4 shows
              good distributional hand without strength 18-19 hcp,
              so Opener first jump to 2nt and in 3rd bid then 4.
   3  => good 6+ cards with 16-17 hcp not GF
              AKQxxx or AKJxxxx or KQJ10xxx
               Responder can pass, bid 3nt with stopper in unbid suits,
               bid 3 with stopper trying a possible 3nt if Opener has
               stopper in , or rebiding 3 asking for support of 3 cards.
   3 => splinter singleton - support 4 up to 18 points 
              Axx AJ10x x KQ98x
              Responder rebids 3 is sign-off
    3 => 4 cards support 16-17 hcp can be 5422 or hand that could
              be opened in 1nt (AJ10x AJ10x xx KQ10) but having both
              majors was opened in a minor to find fit in major.
   3 => splinter GF with 4 cards and 18+ points
              Responder 4 is cuebid support (A/K) and in 4 is a cuebid (A)
              both showing Slam interest. This hand is GF more strong than
              jump to 4 because allow possibility of Responder's cuebid:
              x AJxx Ax AKJ10xx
  3nt => solid Clubs suit AKQJxxx, AKJ10xxx, with stopper in ,
              and semi stopper in
              Kx  xx Q10x AKQJ9xx  or  QJx x Ax AKJ109xx
    4 => cuebid strong suit with 4 cards (Kx KQxx xx AKQ109)
              waiting for cuebid to bid 4nt RKB1430 to try Slam 
   4 => splinter with 4 cards support and strong hand 18+ points
   4 => distributional hand 4 support limited at 16 hcp
              xx AK10x xx AKJ9x
   4 => EKB1430 for with void in Opener has strong support for
              - KJ10x K10x AKJxxx or - AJ10x QJ9 AK109xx  
              Exclusion Keycard Blackwood responses are: step1 = 1 or 4;
              step2= 0 or 3; step3= 2 without Queen; step4= 2 with Queen.
  4nt => RKB1430 for Hearts
   5 => to play 7/8 cards up to 15 hcp 
              x Qx Kx AKJ98xxx  or x Kx Kxx AKQ1098x

Opener's second bid after response 1
Opener Responder
   1       1
      ?
   1nt => no 4 cards - limit hand to 12-14 hcp - 
   2  => normally 6 cards or 5 with a singleton (probably )
   2  => 5/4 reverse hand 16-21 hcp
               Responder must use Leb for reverse now
   2  => 5/4 reverse hand 16-21 hcp
               Responder must use Leb for reverse now 
   2  => 4 cards - 12-14 hcp -
   2nt => balanced hand 18-19 hcp
               Responder can use New Minor Forcing bidding 3
               Opener with balanced hand and 4 cards should not jump
               to game in because a jump for 4 shows good distributional
               hand but not strength 18-19 hcp,
              so Opener first jump to 2nt and in 3rd bid then 4.
   3  => 6+ cards with 16-17 hcp (AKQxxx or AKJxxxx) then
               Responder can pass, bid 3nt, bid 3 showing 5+ and denying
               4 or 4, or both stoppers to bid 3nt.
   3  => splinter singleton and 4 cards support up to 17 points
               this splinter is more weak than the 4 splinter that is GF
               all splinter at level 3 shows up to 15 hcp so not GF
    3  => splinter singleton and 4 cards support 16+ points
   3  => 4 cards support 15-17 hcp can be 5-4-2-2 or
               a balanced hand that could be opened in 1nt
               (AJ10x AJ10x xx KQ10) but having both majors
               is preferred to be opened in a minor to find fit in a major
               (denies singleton in 5431 hand).
  3nt => solid Clubs suit AKQJxxx, AKJ10xxx, with stopper ,
               Kx  xx Q10x KQJ9xx  or  QJx x Ax AKJ109xx
    4 => cuebid in Clubs with 4 support (KQxx Kx xx AKQ109)
              waiting for cue bid 
   4 => splinter with support 4 cards and 18-21 points
              KQxx Kxx x AKQ109
   4 => splinter with support of 4 cards and 18-21 points 
              KQxx x Kxx AKQ109
    4 => distributional hand 4 support limited at 16 hcp
              AK10x xxxx AKJ108
  4nt => RKB1430 for
   5 => to play 7/8 cards
             (Qx x Kx AKJ98xxx  / Kx x Kxx AKQ1098x)

Opener's second bid after response 1nt
Opener Responder
   1       1nt
     ?
  pass => nothing to do - up to 14 hcp
   2   => normally 6 cards or 5 with a singleton in a major - sign-off
    2   => 5/4 reverse hand 16-21 hcp or a 6/5 with up to 4 losers
               Responder must use Leb for reverse now
   2   => 5/4 reverse hand 16-21 hcp or a 6/5 with up to 4 losers
   2   => 5/4 reverse hand 16-21 hcp or a 6/5 with up to 4 losers
  2nt  => invitation hand possible 6322 or 5422 with 15-16 hcp
   3  => good suit 6/7 cards - Responder with stopper in both majors
               may bids 3nt or just bids his major's stopper. Then Opener
               rebids Clubs without the other major stopper or bids 3nt.
   3  => reverse in jump shows a self splinter with good 6/7 cards in
               Responder decide: 3nt; 4 sign-off; 5 or
                bidding a major at level 3 shows a stopper with stopper in
               Qxx Axx x AKQxxx or QJx Ax x AKJ10xxx 
   3  => singleton with solid Clubs suit - not GF
                AJx x Jx AKQxxxz or QJx x A10x AKQ10xx
               Responder decide: 3nt; 4 sign-off; 5 
   3  => singleton with solid Clubs suit - invitation hand
               Responder decide: 3nt; 4 sign-off or 5.
  3nt  => to play 18-19 hcp
   4  => Gerber  - asking for aces - Slam interest
               possible special hand: Ax x KQ10x AKJ98xx
   4 => EKB1430 with void in and solid Clubs suit - GF
   4 => EKB1430 with void in and solid Clubs suit - GF 
   4 => EKB1430 with void in and solid Clubs suit - GF
   5 => to play: - AJx KQJ9 KQJ1098

Auction development when Opener rebids 1 after Responder bids 1
Opener Responder
   1      1
   1      ?
            1 => 4th suit GF - ask for stop or explanation of the hand
                       no promises 4 cards
            1nt => shows stopper and limited Response's hand in 7-10 hcp
            2 => 3+ cards - sign-off - up to 9 hcp
            2 => 5+ sign-off - up to 9 hcp
            2 => 3 cards - long suit with a singleton
            2 => reverse hand 5+4 FG more than 12 hcp
            2nt => 11-12 hcp invitation to 3nt with Spades stopper
            3 => 5+4 10-11 hcp invitation
            3 => 6+ 10-11 hcp invitation
            3 => 5+4 reverse hand more strong than jump to 4
                      asking for cue bid un passant
            3 => 6+5 distributional hand weak -
                      good Diamons and bad Spades 8-10 hcp
                      98xxx xx AKJxxx - 
                      108xxx x AK109xx x
                      J7xxx xx KQJ109x -
           3nt => to play - good stop in Spades
            4 => Gerber asking for aces - interest in Slam - maybe as trump
            4 => cue bid 5+4 (solid Diamonds - good support in ) 12-14 hcp
            4 => 5+4 12-14 hcp but Diamons not solid
            4 => 5-6 strong distributional hand 11+ hcp: 
                      QJ109x - AKJxxx xx 
                       Opener with 2 and 2 or 1 must prefer
                       so pass only with 3 cards   
            4nt => RKM1430 for  
             5 => to play (- xx AKxxx J109xxxx)                        
            5 => to play (Jx Q98 KQJ10xxxx -)
             5 => exclusion RKC for with void in
Note1: The Exclusion Roman Key Card have answer in 4 steps - can use RKC0314/1430:
           RKC0314                                           RKC1430
           step1 = 0-3 key cards                 step1 = 1-4 key cards
           step2 = 1-4 key cards                 step2 = 0-3 key cards
           step3 = 2 key cards                    step3 = 2 key cards
           step4 = 2 key cards + Queen     step4 = 2 key cards + Queen
In case the exclusion is made in 5 (void) then step1=5nt; step2=6; step3=6; step4=6   
Auction development when Opener rebids 1 after Responder bids 1
Opener Responder
   1       1
   1       ?
           pass => deny 4 or 4 cards and shows weak hand 5-8 hcp
            1nt => shows stopper and limit Response's hand in 7-10 hcp
             2 => 3+ cards - sign-off - up to 9 hcp
             2 => 5+ sign-off - up to 9 hcp
             2 => 4th suit GF asking for explanation of Opener's hand
                        not promises stopper
                        Opener with stopper in bid 2nt prioritily,
                        in second priority bid 3 with 3 cards support,
                        or rebid Clubs (3).
             2 => 5+ and 4 with 12+ hcp  
            2nt => 11-12 hcp invitation to 3nt with stopper
             3 => 5+4 10-11 hcp invitation
             3 => 6+ 10-11 hcp invitation
             3 => 6+5 8-10 hcp and probably is a bad suit and top
                        honors are in Diamonds suit
                         xx 98xxx AKJxxx -
                        x 107432 AKJ109x x  
                        Jx J8xxx KQJ109x -
             3 => 4 cards bad and good honors in Diamons - 10-11 hcp
            3nt => to play - good stop in Hearts
             4 => Gerber ask for aces - interest in Slam - maybe as trump
             4 => cuebid 5+4 (good Diamonds and support in 12-14 hcp
             4 => 6+5 strong distributional hand - x QJ109x AKJxxx x 
                        Opener with 2 and 2 or 1 must prefer
                        so pass only with 3 cards  
              4 => 4-5+ 12-14 hcp but not strong (jump bid of 4 is strong)    
             4nt => RKC for  
             5 => to play (- xx AKxxx J109xxxx)                        
             5 => to play (Jx Q98 KQJ10xxxx -)
             5 => exclusion RKC for with void in
Note2: The Exclusion Roman Key Card have answer in 4 steps - can use RKC0314/1430:
           RKC0314                                         RKC1430
           step1 = 0-3 key cards                 step1 = 1-4 key cards
           step2 = 1-4 key cards                 step2 = 0-3 key cards
           step3 = 2 key cards                    step3 = 2 key cards
           step4 = 2 key cards + Queen      step4 = 2 key cards + Queen
In case the exclusion is made in 5 (void) then step1=5; step2=5nt; step3=6; step4=6   
Auction development when Opener rebids 1nt after Responder bids 1
Opener Responder
    1    1
  1nt       ?  
             pass => nothing to do - up to 10 hcp
              2   => sign-off 4+ cards up to 10 hcp
              2   => sign-off good 5+ cards up to 10 hcp 
              2   => 5+4 FG 12+ hcp (Walsh)
              2   => 5+4 FG 12+ hcp
              2nt  => invitation 10+-11 hcp with good 9/10/J cards
              3   => invitation with 5-4 cards and 10-11 hcp 
                           can have singleton in a major
              3   => invitation 10-11 hcp to game with good 6 like:
                          AQJ986 or AK10xxx
              3   => 6-5 weak distributional hand 8-10 hcp no GF:
                           x Q9xxx AQxxxx x  or     - A9xxx KQJ9xx xz
              3   => 5-6 weak distributional hand 8-10 hcp no GF: 
                           J10xxx x AKxxxx x  or  Q87xx x KQJxxxx -
              3nt  => to play
              4   => Gerber - ask for aces - Slam interest
              4  => Diamonds suit solid (AKQ10xxx) - asking for cuebid or 5
              4  => 6-5 good distributional hand 10 hcp:
                          x Q987x AQJ10xx x
                          Opener with 2 and 2 must prefer
              4  => 5-6 good distributional hand 10 hcp: 
                         J109xx - AKJxxx xx 
                          Opener with 2 and 2 must prefer     
              4nt  => RKC for  
              5  => to play (- xx AKxxx J109xxxx)                        
              5  => to play (Kx - KQJ10xxxx Q98)

 Auction development when Opener rebids 1 after Responder bids 1
Opener  Responder 
  1        1
  1         ?
           pass => deny 4 or 4 cards and shows weak hand 5-8 hcp
            1nt => 6-10 hcp should have stopper in sign-off
            2 => support 4+ 6-9 hcp sign-off 
            2 => the 4º suit ask for explanation - need 10+ hcp shows 5 cards
            Opener bids 2 with 3 cards and no top honor (A/K/Q)
                                3 with 3 cards and one or more top honors
                                2 with weak hand 11-13 hcp and 5-5 or 6-5 
                               2nt with stopper in and deny support in
                                3 with 5 cards and no stopper in and no support in
                               3nt with 14-16 hcp 1,5 stopper in possible singleton  
             Responder after has bidded the 4º suit, if support Opener in one of
             his suits (here or ) makes the bidding GF and in a cooperative
             way try now to search Slam, but if Responder rebids his suit
             showing 6 permits that Opener pass with singleton if Opener is
             limited at 14 hcp.     
            2 => Responder rebiding his suit is 100% sign-off 5-9 hcp
                       Jx QJ987 Jxxxx  x  or       Jx KJ987x Jxxx  x   
            2 => support 4 cards 6-9 hcp
           2nt => 10+-11 hcp with stopper - invitation to 3nt
            3 => invitation  10+-11 hcp support 4+ cards - could have 5
            3 => shows 6-4 and is sign-off for a partnership playing Walsh
                        Jx QJ98 KJxxxx  x  or       x J987x KQ10xxxx  x   
            3 => invitation with 6 cards 10-11 hcp - Opener pass with singleton
            3 => invitation with 4 cards 10-11 hcp - Opener may pass
           3nt => to play
            4 => GF strong support in Clubs Slam interest asked for cuebid or 5
            4 => GF splinter with 4 support and 13-16 hcp, ask for cuebid or 4
            4 => to play 7/8 cards
            4 => to-play -4 cards 11-14 hcp
           4ST=> RKC for (last suit bid by Opener)
            5 => to play - good distribution hand with 5+ cards 11-13 hcp
            5 => exclusion RKC for with void in
In exclusion for 5 rkc step1=5; step2=5; step3=5nt; step4=6

 Auction development when Opener rebids 1nt after Responder bids 1
Opener  Responder 
  1        1
 1nt        ?
           pass => denies 4+ cards and shows weak hand 5-9 hcp
            2 => support 4+ 6-9 hcp sign-off 
            2 => the NMF - need 10+ hcp shows 5 cards
            2 => Responder rebiding his suit is 100% sign-off 5-9 hcp
                       Jx QJ987 Jxxxx  x  or       Jx KJ987x Jxxx  x   
            2 => shows 4-5 one-round force 10+ hcp
           2nt => 10+-11 hcp - invitation to 3nt
            3 => invitation  10+-11 hcp support 4+ cards - could have 5
            3 => shows 6-4 and is sign-off for a partnership playing Walsh
                        Jx QJ98 KJxxxx  x  or       x J987x KQ10xxxx  x   
            3 => invitation with 6 cards 10-11 hcp - Opener pass with singleton
            3 => 5-6 cards 8-10 hcp - Opener pass without honors in majors
           3nt => to play
            4 => GF strong support in Clubs Slam interest asked for cuebid or 5
            4 => GF splinter with 4 support and 13-16 hcp, ask for cuebid or 4
            4 => to play 7/8 cards
            4 => splinter singleton and 5+ cards with 11-14 hcp
           4ST=> RKC for (last suit bid by Opener)
            5 => to play - good distribution hand 11-13 hcp
Auction development whenr Opener rebids 1nt after Responder bids 1
Opener Responder 
  1        1
  1nt <= 12-14 hcp - or 15 hcp with singleton in - denies 5 cards        
                ?
            pass => nothing to do
             2  => support with 4+ and 6-9 hcp
             2  => NMF – read  www.bridge.pro.br/nmf.htm 
                         after NMF the support in 3 become GF and search to Slam
                          also the bid of 3 is now GF showing 5-5 and 12+ hcp
             2  => 5-4+ sign-off 5-9 hcp - Opener must pass or correct
             2  => 5+ cards 5-9 hcp sign-off 100%
            2nt => invitation 11 hcp
             3  => 4+cards 10-11 hcp invitation
             3  => 6-4 sign-off for partnership that play Walsh
                         Jxxx 8 KJxxxx  xx  or   Axxx 7x Q10xxxxx  x
             3  => 5-5 10-11 hcp – Opener decide: pass/3 or bid game
             3  => 6 invitation 10-11 hcp - Operner decide between pass or 4
            3nt => to play
             4  => GF strong support in interest in Slam asked for cuebid or 5
             4  => 6-5+ with misfit and weakness  Opener can pass in 4
             4  => 6-5+ Responde must choose the major
             4  => to play
            4ST => RKC for
             5  => to play 4-5+ sign-off

Note: if you do not play NMF read checkback-nmf-fsf
Opener Responder <= this sequence is valid only for passed hand
   1        1
  1nt        2 is sign-off and shows 4-5+ 6-9 hcp

Auction development when Opener rebids 2 after Responder bids 1nt
Opener Responder
  1       1nt
  2  <= 6 - 12-15 hcp
               ?
            pass=> 6-8 hcp
              2 => cuebid (A/KQx) 9-10 hcp with 3 cards - invitation 3nt or 5
              2 => cuebid (A/KQx) 9-10 hcp with 3 cards - invitation 3nt or 5
              2 => cuebid (A/KQx) 9-10 hcp with 3 cards - invitation 3nt or 5
              2nt =>  invitation showing stoppers in both majors and 9-10 hcp   
              3 => 3+ weakness - afraid opponents reopen at level 2 - 6-8 hcp

Auction development after Opener reverse in 2 after Responder 1nt
Opener Responder
  1      1nt
  2 <= reverse hand 16-21 hcp - forcing one round    
             ?
            2 => show stopper in deny stopper in  8-10 hcp
            2 => show stopper in deny stopper in  8-10 hcp 
           2nt => confirm stopper in majors minimum 6-7 hcp   
            3 => weak hand 6-7 hcp with 4 cards
            3 => weak hand 6-7 hcp with 4 cards
           3nt => confirm stopper in majors and 8-10 hcp
            5 => to play
 
Auction development after Opener reverse om 2 after Responder 1nt
Opener Responder
  1      1nt
  2 <= reverse hand 16-21 hcp - forcing one round      
               ?
             2 => show stopper in minimum 6-7 hcp
            2nt => deny stopper in minimum 6-7 hcp
             3 => 3+ minimum 6-7 hcp
             3 => 3+ no stopper in but honors in and maximum 8-10 hcp
            3nt => confirm stopper in unbid suits and maximum 8-10 hcp
             5 => to play
  
Auction development when Opener reverse in 2 after Responder bids 1nt
Opener Responder
  1       1nt
  2 <= reverse hand 16-21 hcp 
              ?
            2nt => confirm stopper in minimum 6-8 hcp   
             3 => 3+ denies stopper - minimum 6-8 hcp
             3 => 3+ no stopper but with honors in and maximum 8-10 hcp
            3nt=> confirm good stopper in unbid suits and maximum 8-10 hcp
             5 => to play

Auction development when Opener bids 1 and 2nt and Responder bids 1nt
Opener Responder
  1      1nt
 2nt <= 16-17 hcp possible both major and no stopper in
           pass => minimum 6-7 hcp and stopper in
             3  => 4 denies stopper - minimum 6-7 hcp
            3nt => to play - maximum 8-10 with stopper
 
Auction development when Opener rebids 3 after Responder bids 1nt
Opener Responder
  1       1nt
  3 <= 6+ and 16-18 hcp - Responder pass, make try for game, bid game
            pass => weak hand 6-7 hcp
             3   => shows stopper in want to know Opener stopper in major
             3   => shows stopper in deny stopper in has semi stopper in
             3   => shows stopper in deny stopper in has semi stopper in
            3nt  => shows stoppers in majors and has semi stopper in 8-10 hcp
             5  => to play (J10x J9x AKJ9 10xx)

Auction development when Opener bids 3/3 after Responder bids 1nt
Opener Responder
  1      1nt
  3 <= 6+5 distributional hand -
            Responder with 6/7 hcp can pass or bid 4
  3 <= 6+5 distributional hand -
            Responder with 6/7 hcp can pass or bid 4
     Note: Responder should consider Ace in other suit as a useful card but
               not a King, so useful cards are honors in suit bidded by opener.
               Thus, 3nt bid is unthinkable because Opener have a weak hand.
               So, with an Ace in an unbid suit, any 4 cards support in Clubs and
               a King in the major bidded by Opener Responder should try 5.

Auction development when Opener bids 1 and 3nt and Responder bids 1nt
Opener Responder
  1      1nt
  3nt <= 18-19 hcp possible both major
           pass => nothing to do

Auction development when Opener bids 4 Berber after Responder bids 1nt
Opener Responder
  1      1nt
  4 <= Gerber - special hand - final contract 5 or 6 depends on aces 
          possible hands: AKQx x 9 AKQ10xxx /x KQJ10 x AKQ10xxx

Auction development when Opener bids 1 Responder bids 2
Opener Responder
  1       2 <= inverted minors must be read

Auction development when Opener bids 1 and Responder bids 2/2/2
Opener Responder
   1      2 <= weak 6 cards - less than 6 hcp
   1      2 <= weak 6 cards - less than 6 hcp
   1      2 <= weak 6 cards - less than 6 hcp
In all this situation Opener need prudence and may stop the auction with pass, but if Opener has Hxxx or HHx (like AKx or AQx) support and 18-19 hcp there are hope in 3nt game considering 6 tricks in the weak suit and entries to finesse in other suit.

When Opener has fit in the weak long suit - by agreement with partner - he may bid 2nt to search for a singleton in Responder hand.

This permits better decision from Opener to decide to play in 3nt or in the major at level 4.

Corrolary: whitout fit there are no hopeless - Opener should not try a fit in other suit, even with a 5-5 hand is prudent to pass with singleton because we should make decision based in statistical and in this case sometimes may work and in many times will not work.
           
++++++++++++++++++++++++++++++++++++++++++++++++++
1 OPENING

 Opener Responder   Responses after 1 open - no interference in the auction
  1       ?
            1 => 4+ cards 6+ hcp
            1 => 4+ cards 6+ hcp
           1nt => deny major 6-10- hcp and deny 5 cards
            2 => 4+ cards and 12+ hcp
            2 => 4+ cards and 10+ hcp - read inverted-minors
            2 => 6+ cards weak - less than 6 hcp
                       x QJ98xx 987 Jxx
                       Qx Q1098xx 9xJxx
                       x K98xxxx xx Jxx 
            2 => 6+ cards weak - less than 6 hcp
                       K98xxx x xxx Jxx
                       A98xxxx xx xx xx 
                       Q1098xxx x xx Jxx  
           2nt => 11 hcp balanced hand - deny major - deny 5 cards
                      - promise stopper in majors
                      K108 A10x Q9x Q10xx
                      QJ8 K10x Q10x K9xx
                      QJ8 K98 1087 KQ109 
            3 => 6+ cards 8-11 points - special bid of 2/1 system with honors
                      concentraded in Cçubs  (Q10x x xx AQJxxx)  
            3 => 5+ cards 5-9 hcp - read inverted-minors 
      3/3 => 5+ splinter (singleton/void in the bided suit) 11-14 hcp - GF
          3nt => balanced 16-17 hcp with 4 cards in 4333 or 4432
                      KJ8 AQ K9x K10xx  or AQx KQ8 Q10x KJx
                      read 1minor-3nt
           4 => Gerber ask for aces (response 4=0/4, 4=1, 4=2, 4nt=3)
           4 => transfer to 4 no 2 aces : 8 KQJ109xx K7 109x up to 10 hcp
           4 => transfer to 4 no 2 aces : QJ1098xxx9A710x up to 10 hcp 
           4 => transfer to 5 no 2 aces : Kx - J32 AK10987xx up to 10 hcp  
         4nt => RKB1430 for Diamonds (afraid of interference - strong hand)
           5 => to play - 6/7 cards support - deny aces or void    
5/5/5 => exclusion RKC for (the suit bided can't be counted for ace)

Auction development when Opener rebids 1 after Responder bids 1
Opener  Responder 
  1        1
  1        ?
          pass => deny 4 or 4 cards and shows weak hand 5-8 hcp
           1nt => 6-10 hcp should have stopper in sign-off
            2 => the 4º suit ask for explanation - need 10+ hcp and 5 cards
             Opener bids: 2 with 3 cards and no top honor (A/K/Q)
                                   3 with 3 cards and one or more top honors
                                   2 with weak hand 11-13 hcp and 6-5 or 7-5 
                                  2nt with stopper in and deny support in
                                   3 with 5 cards and no stopper in and no support in
                                  3nt with 14 hcp and 1,5 stopper in possible singleton
            Responder after 4º suit may support Opener in one of his suits
                ( or ) makes the bidding GF and in a cooperative way try now
                search for Slam, but if Responder rebids his suit showing 6 allows
                that Opener pass with singleton if Opener is limited at 14 hcp.
            2 => support 4+ 6-9 hcp sign-off     
            2 => Responder rebids is sign-off 5-9 hcp (Jx QJ987 Jxxxx x)    
            2 => support 4 cards 6-9 hcp
           2nt => 10+-11 hcp with stopper - invitation to 3nt
            3 => 5-5 invitation Opener may pass in 3 in misfit/weakness
             3 => invitation  10+-11 hcp support 4+ cards - could have 5
             3 => invitation 6 cards 10-11 hcp - Opener can pass with singleton
             3 => invitation with 4 cards 10-11 hcp - Opener can pass
           3nt => to play
             4 => GF - splinter with 4 cards support and 13-16 hcp, asks for
                       cuebid or sign-off in 4
             4 => GF – strong support in – Slam interest - asks for cuebid or 5
             4 => to play 7/8 cards
             4 => to-play -4 cards 11-13 hcp - good distribution
            4ST=> RKC for (last suit bid by Opener)
             5 => exclusion RKC for with void in
Exclusion in 5 then rkc: step1=5; step2=5; step3=5nt; step4=6
             5 => to play - good distribution hand with 5+ cards 11-13 hcp
Auction development when Opener rebids 1nt after Responder bids 1
Opener  Responder 
  1        1
  1nt       ?
           pass=> denies 4 cards and shows weak hand 5-8 hcp
              2 => NMF - vide explanation in www.bridge.pro.br/nmf.htm    
              2 => support 4+ 6-9 hcp sign-off
              2 => sign-off (Responde rebids his suit is sign-off) 5-9 hcp
              2 => 5-4 GF - 12+ hcp - ask for 3 cards support,
                         Opener with good stop in and no support may bid 3nt,
                         but without stopper in and no support in Opener
                         should rebid his Diamonds or with Spades honors bids 3
             2nt => 11 hcp with stopper - invitation to 3nt
              3 => 5-5 10-11 Opener may pass in misfit case or weakness
              3 => 4+  10+-11 hcp support 4+ cards - could have 5
              3 => 6 cards 10-11 hcp Opener pass with singleton
              3 => 6-5 GF distributional hand 
             3nt => to play
              4 => Gerber - strong hand and possible good support in or solid
              4 => GF – strong support in – Slam interesti- ask for cuebid or 5
              4 => to play 7/8 cards
              4 => spliinter - support in - Opener can ask RKC or sign-off in 5  
              4nt => RKC for
              5 => exclusion RKC for with void in
When exclusion is made in 5 then step1=5; step2=5; step3=5; step4=5nt
              5 => to play - good distribution hand with 5+ cards 11-13 hcp

Auction development whenr Opener rebids 1nt after Responder bids 1
Opener Responder 
   1       1
 1nt <= 12-14 hcp - or 15 hcp with singleton in - denies 6 cards        
                ?
            pass=> nothing to do
             2 => NMF – read  www.bridge.pro.br/nmf.htm 
                        after NMF the support in 3 become FG and search to Slam
                         also the bid of 3 is now FG showing 5-5 and 12+ hcp
             2  => support with 4+ and 6-9 hcp - sign-off
             2  => 5-4+ sign-off - pass or correct - do not support
             2  => 5+ cards 5-9 hcp sign-off
            2nt => invitation 11 hcp
             3  => 5-5 10-11 hcp – invitation - Opener decide: pass/3 or game
             3  => 4+cards 10-11 hcp invitation
             3  => 5-5  invitation 10-11 hcp – Opener decide: pass/3 or game
             3  => 6 invitation 10-11 hcp - Operner decide between pass or 4
            3nt  => to play
             4  => GF – strong support in interest in Slam cuebid or 5 sign-off
             4  => 6-5+ with misfit and weakness  Opener can pass in 4
             4  => 6-5+ Opener must choose the major
             4  => to play
            4ST => RK1430 for
             5  => to play 4-5+ sign-off   

Auction development when Opener rebids 2 after Responder bids 1nt
Opener Responder
  1      1nt
  2 <= 12-16 hcp
              ?    
            pass=> 4 and minimum 6-8 hcp
              2 => 4 minimum 6-8 hcp 
              2nt => confirm stopper in majors maximum 9-10 hcp   
              3 => 5 and maximum 9-10 hcp
              3 => 4 and maximum 9-10 hcp 

Auction development when Opener rebids 2 after Responder bids 1nt
Opener Responder
  1       1nt
  2  <= 6 cards and 12-16 hcp
             ?
          pass=> 6-7 hcp
            2 => cuebid (A/KQx) 9-10 hcp 3+ cards - invitation 3nt or 5
            2 => cuebid (A/KQx) 9-10 hcp 3+ cards - invitation 3nt or 5  
           2nt =>  invitation showing stoppers in both majors and 9-10 hcp   
            3 => 3+ 5-8 hcp and afraid opponents reopen at level 2 in a major

Auction development when Opener reverse 2 after Responder bids 1nt
Opener Responder
  1       1nt
  2 <= reverse hand 16-21 hcp - one-round force     
              ?
             2 => shows stopper in minimum 6-8 hcp
             2nt => deny stopper in minimum 6-8 hcp
             3 => 5+ minimum 6-8 hcp
             3 => 3+ no stopper in but honor in and maximum 9-10 hcp
             3nt=> confirm stopper in unbid suits and 9-10 hcp
  
Auction development when Opener reverse 2 after Responder bids 1nt
Opener Responder
  1      1nt
  2        ?
            2nt => confirm stopper in minimum 6-7 hcp   
             3 => 5+ cards minimum 6-8 hcp
             3 => 3+ no stopper in but honors in with maximum 8-10 hcp
            3nt => confirm stopper in unbid suits and 8-10 hcp

Auction development when Opener rebids 2nt after Responder bids 1nt
Opener Responder
  1      1nt
  2nt <= 15-17 hcp possible both major and shorter in
          pass => minimum 6-7 hcp 
            3nt => to play - maximum 8-10 with stopper in  

Auction development when Opener rebids 3 after Responder bids 1nt
Opener Responder
  1       1nt
  3 <= 6+ and 16-18 hcp - Responder pass or make try for game
            pass => weak hand 6-7 hcp
             3  => show stopper in but deny stopper in have semi stopper in
             3  => show stopper in but deny stopper in have semi stopper in
             3nt  => show stopper in majors and have semi stopper in 8-10 hcp
             5  => to play (J10x J9x Jxx AK109)

Auction development when Opener shows 6/5 distribution bidding a major
at level 3 after Responder bids 1nt
Opener Responder
  1      1nt
  3 <= 6+5 distributional hand - Responder with 6/7 hcp pass or bid 4
  3 <= 6+5 distributional hand - Responder with 6/7 hcp pass or bid 4
Note: Responder should consider Ace in other suit as a useful card but not
but a King, so useful cards are honors in the suits bided by opener. Thus, the bid of 3nt is unthinkable because Opener have a weak hand. So with an Ace in the unbided suit, any 4 cards support in Diamonds and a King in the major bidded by Opener Responder should try 5.

Auction development when Opener jump to 3nt after Responder bids 1nt
Opener Responder
  1      1nt
  3nt <= 18-19 hcp possible both major
            pass => nothing to do  
 
Auction development when Opener asked for aces after Responder bids 1nt
Opener Responder
  1      1nt
  4 <= Gerber - special hand - final contract 5 or 6 depends on aces 
            (possible hands: AKQx x AKQ10xxx x / x KQJ10 AKQ10xxx x)

Opener Responder
  1       2 => GF - 12+ hcp => read  1d-pass-2c-GF.htm

Auction development when Opener bids 1 and Responder bids 2
Opener Responder
  1        2    => 4+ 10+ hcp - need read => inverted-minors

Auction development when Opener bids 1 and Responder bids 2/2
Opener Responder
   1      2 <= weak 6 cards - less than 6 hcp
   1      2 <= weak 6 cards - less than 6 hcp
In both situations Opener need prudence and may stop the auction with pass,
but if Opener have 4 cards support and 18-19 hcp there are hope in 3nt game
considering 6 tricks in the weak suit and entries to finesse in other suit.

In fact Opener having fit may search for a singleton in Responder's hand bidding 2nt (after agreement with partner) and if Responder has no singleton he rebids his suit. This allows better decision from Opener in play 3nt or in a major at level 4.
Corrolary: whitout fit there are no hopeless so Opener should not try a fit in other suit, even with 5-5 hand, it is prudent pass with singleton considering that bridge is played for better probability.

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