=========================

LEBENSOHL CONVENTION

A great contribution towards better competitive bidding was originated by an old article, published nov/1970 in Bridge World magazine by Kenneth Lebensold from New York City, whose author’s misspelled name became the denomination of this coenventionwn, the "2NT Lebensohl" or just LEB like most player like to say.

The 2NT Leb in competition is not used to show a balanced hand or a stopper in the opponent's suit, but it is a artificial bid just to make partner to bid 3 Clubs, like a transfer, in order to establish a important means of communication to better understand partner's hand, or to find a more accurate contract. Leb makes it possible to distinguish between:
a) an invitation hand;
b) a sign-off hand;
c) a game forcing hand.
More than that, Leb also permits, in uncontested bidding, you and your partner to take real control in a reverse hand ranging 16-20 hcp, with 5-4-x-x distribution, and to know if the opener are in the lower range of 16-17 hcp or in the higher range of 19-20 hcp with 5431 or 5422.

To learn the 3 principal applications and rules of this convention follow a detailed description of its use in each case:
LEB1: when an opponent intervenes after our partner opens 1NT.
LEB2: when an opponent open weak 2 suit and partner says double.
 Leb3: After your partner makes a reverse at 2-level showing 54xx
          distribution with 16-20 hcp range

 LEB1) LEBENSOHL IN DEFENSE AGAINST OPPONENT INTERVENTION IN OUR 1NT  (can be used for weak NT with some adjustments)

When partner open 1NT and an opponent overcalls at 2-level (2C/2D/ 2H/2S), the Stayman convention and transfer convention are off.
In the particular case, when intervention of 2 Clubs shows an artificial suit like in CAPP, double by responder ignores the overcall and is the normal Stayman changing 2 for double to ask for a major suit -
despites you can also agree with your partner too accept transfer in this case we don't recommend it because you lose 2D sign-off bid.

Rule1: All responder 2-level bids are sign-off, but if opener has 4 cards support, he must raise to level 3 in that suit. Some partnerships accept raise only in maximum (17 hcp).
Opener Overcaller   Responder
  1NT        2C         (2D or 2H or 2S) <= sign-off
  1NT        2         (2H or 2S) <= sign-off
  1NT        2H         2S  <= sign-off

Rule2: All double are penalty for that suit, except in the case of artificial 2C (used in capp / multi Landy / ...)

Rule3: When interference ocourrs response of 2NT is undetermined and opener must bid 3 or pass if the other opponent bids at level 3.
After opener bids 3, the second possible bids of the responder are:

a) passes if he has long suit in clubs and weak hand (< 8 hcp)
Opener Overcaller Responder  Advancer
  1NT        2C*          2NT**         pass      *Capp (majors)
  3C          pass          pass           pass      ** transfer to 3          
the responder hand can be: S63  HQ95 D83 CK10976

b) bid another suit at 3-level, which has a lower rank than opponent's suit, to show a sign-off at 3-level.
Opener Overcaller Responder Advancer
  1NT        2S             2NT*         pass 
   3          pass    (3D or 3H) <= sign-off
responder =>  S6  H975 DAQ873 C10965 => 3D
responder =>  S6  HJ98754 D873 CJ65 => 3H

c) 3NT to show strong game hand, no interest in majors, and at least one stopper in opponent's suit.  
Opener Overcaller Responder Advancer
  1NT       2S            2NT           pass 
   3C       pass          3NT <= sign-off showing stopper
responder =>  95    SQ106  DAQJ873  96 
responder =>  SQ95 K4      DA73  CK10962 

Note1: some partnerships use an inverted convention for this situation. They use  the "Reverse Lebensohl", where a direct 3NT bid shows a stopper in the opponent's suit, so responder don't need bid 2NT to show his stopper.

d) responder, after bidding 2NT, bids the opponent's suit (cuebid) to show 4 cards in a major (delayed Stayman) asking opener to bid his lower ranking major or to bid 3NT because the responder doesn't have a stopper in opponent's suit.  
Opener Overcaller Responder Advancer
  1NT        2S            2NT            pass
  3C         pass          3S   <= shows 4 cards in Hearts, enough strength
                                          for game and at least and 1 stopper in
                                         opponent's suit.
                                         Opener decides where to play.
responder =>  SQ106  HKJ95 DQ873 CK6 
responder =>  SK6      HQJ95 DA7    CJ10962 
Opener Opponent Responder Opponent
  1NT         2D*         2NT          pass         *natural (Diamonds suit)
   3         pass          3D  <= cue-bid shows Diamonds stop and at   
                                             least one major suit
responder=> SQ1076 H95 DA8 CK9643=> if pd bids 3 then you bid 3
responder=> SK986 HAQ95 DJ973  C6 => if pd bids 3NT then you pass

e) responder, after bidding 2NT, bids a suit ranking higher than opponent's suit at 3-level to show 5 cards and stop in opponent's suit.
Opener Overcaller Responder Advancer
   1NT        2D*         2NT          pass *natural (Diamond suit)
    3C        pass     (3H or 3S) <= shows stopper in opponent's suit
                                                    and 5+ cards in this major suit
responder =>  SQ106   HK9875 DQ83 CK6 => 3H in second bid
responder =>  SKQ762 H5   DA7 C109642 => 3S in second bid

Rule4: When responder directly cuebids in opponent's suit he denies a stopper in opponent's suit and shows 4 cards in one major suit, opener having both major suits must bid his lowest ranking suit first.
Opener Overcaller Responder Advancer
   1NT        2D*       3D <= shows- NO stop in Clubs and one or two
                                         major suit (a stayman without stopper)
 *Natural (Clubs suit)
responder => SKQ106 HK987 CJ876 5
                 => If pd bids: 3NT you pass; a major you raise to 4H/4S
responder => SKQ76 H52 CA10964 75 => If pd bids 3D you bid 3 

Rule5: When responder bids a suit at the 3-level, it shows 5 cards and enough strength for game, but  denies a stopper in opponent's suit.
Opener Opponent Responder Opponent
  1NT         2H          3S <= shows 5 cards in Spades and game force
                                          but no stopper in opponent's suit.
responder =>  SKQ1064  H8 DJ73 CK876 => bid 3S and Opener decides
Opener Overcaller  Responder  Advancer
  1NT          2S*      (3C or 3D or 3H) <= forcing game –
                                                               5 cards suit – no stopper
*DONT convention => long Spades suit

Note2: When responder, having minor suits, does not bid 3NT directly (denying stopper), he is showing Slam interesting and Opener can bid 3NT to show values in opponent's suit and no interest in Slam, or without a stopper he can support partner's suit. Opener accepts Slam invitation by making cue-bids (Ace in opponent's suit) or bidding other suit to show controls (Ace or King).

Rule06: When responder bids 3NT directly he denies a stopper in opponent's suit, shows no interest in major suits and enough hcp bid game. So the Opener, with no stopper in opponent's suit, must bid, as a first priority, his 4-card minor suit at the at 4-level or, secondly, his major suit, and only when he is maximum with the two minors bid at level 5. The responder will know what to do.

Note3: When opponent overcalls in a artificial suit showing 2 suits (bicolor) the cue-bid must be done in the known suit or if both are known in the shorter.

Note4: When the opponent overcalls at 3-level, any bidding by the responder is game forcing and shows a 5 card suit. Double is for take out, denying a 5 card suit, and asking Opener to bid his lowest ranking major suit or NT with a stopper and interest in playing 3NT. The Opener can pass if he has the Opponent's suit and this is convenient. A cue-bid at the 4 level tends to show interest in Slam (the responder's second bid will explain) but normally is asking Opener to bid his best major even with 3 cards.

/ / /


=============================

LEB2) LEBENSOHL AFTER A OPPONENT OPENS WITH A WEAK TWO BID AND PARTNER DOUBLES SHOWING A GOOD HAND

When an opponent opens (2D / 2H / 2S) showing six card and 7-10 hcp, partner's double shows 13 or more hcp and if the range are 13-15 hcp he must have 3 cards with an honor in all unbid suits.  

When partner has a good 5-5 or 6-5 two-suiter, not necessarily many hcp, he cue-bids and you must show your first lower ranking suit, giving partner the chance to bid another suit or to just pass if his hand is limited. 

When your partner has a balanced hand with 15-17 hcp and a stopper like AJx or K10xx, he bids 2NT and all transfers and Stayman are "on".

When your partner has a balanced hand 18-20 hcp with good stopper in opponent's suit he bids 3NT directly assuming that you must have 6-7 hcp. Your 4 is asking for a major - like in Stayman - and 4 or 4 are transfers, normally with good 5 card suit or a 6 card suit, because partner's 3NT can also be based also in a long minor suit.

Lets study the rules of Lebensohl over weak two:
Opener Partner Opponent You 
 2weak   double     pass        ?
Attitude: with 0 - 6 hcp => find a sign-off; 
Attitude: with 7 - 9 hcp => make a game invitation to partner; 
Attitude: with 10 or + hcp => find a game (or Slam) contract.

Rule01: Any bid at 2-level is sign-off, so shows less than 7 hcp. Your partner having more than 20 hcp or strong 2-suiter continues the bidding, and a cue-bid is game forcing asking for more details of your hand. The bid of another suit from your partner is a invitation to game in his suit.
Opener Partner Opponent You
    2     double     pass       2 => sign-off
  You => SJ954  H53 DQ9432 C42 or You => Kxx 9764 Jxx Q84

Rule02: If you bid 2NT, your partner with less than 21 hcp or without strong 2-suiter must bid 3 to complete the transfer that initiates your sign-off or forcing game bid.  Now your option  after partner's  3 are:

a) pass if your suit is Clubs and you have less than 7 hcp.
Opener Partner Opponent You
   2S        double      pass      2NT
  pass        3C          pass (pass or 3D or 3H <= sign-off)
             You bid 2NT and pass in 3 Clubs with S95 HJ753 D964 CK542

Note1: The Doubler only bypass the 3C bid if he has a strong hand of up to 20 hcp, or a strong 2-suiter with 3 or 4 losers in the hand.

Opponent Partner Opponent You
     2S         double     pass       2NT <= transfer for 3C
    pass         3H          pass       4H
You: S9 HJ953 DJ942 CK842 <= you intend to pass in 3C but after 3H you should bid game, because your partner have a strong hand, like:
SA4 HAK1072DAQ7    CQJ7 => he bids 3 to show 5 cards and forcing
K3 KQ1087   AKQ854 - => he bids 3 to show strong 2-suiter and forcing
3   AKQ6    KQ108 AQJ9 => he bids 3 to show 4 or more cards and forcing

b) In the second bid, you bid a higher ranking suit than opponent's to show 5 cards, a stopper, and a game forcing hand with at least 10 hcp.
Opponent Partner Opponent You
     2D          double   pass        2NT        
  pass           3C        pass   (3H or 3S) <= forcing game with diam stopper
 You:  SA4 HK10752 DQ97 CQ98 or Q9654 7 A104 KJ54

c) For the second bid you cue-bids to show at least one 4-card major with no stopper in opponent's suit, but forcing game hand.
Opponent Partner Opponent You
     2H          double       pass        2NT       
   pass         3C            pass         3H  <= shows 4 cards in Spades and forcing
You: SQ974 HA7 DQ7 CKJ973 or K1083 J1073 7 AQJ2

d) Bid 3NT for your second bid to show no interest in majors, a stopper in opponent's suit and enough hcp to bid game.
Opponent Partner  Opponent You
    2D         double      pass       2NT        
  pass          3C          pass       3NT <= sign-off
You: S94 HK107 DAJ7 CQJ764 or 8 42 KQJ AJ87632


Rule03: With 7-9 hcp you make a invitational bid by directly bidding a suit at the 3-level without a jump or go through 2NT.
Opponent Partner  Opponent    You
     2S          double       pass    (3C or 3D or 3H) <= invitation
You:  S874 HK1072 D7     CKJ1087 <= 3H
You: J5   Q43    KQ84 10942 <= 3
You: AJ8 853    964    K964   <= 3

Note2: If opponent open 2 weak you are restricted to invite only in 3.

Rule04: With 10 or more hcp and no stopper in opponent's suit, you cue-bids to ask for partner's major suit.
Opponent Partner Opponent You
     2        double     pass         3D  <= shows at least one 4-card major
You: J6542 AJ43 7 AJ2 or KQ75 7 854 AQ964

Rule05: With 10 or more hcp and no 4 card major and no stopper in opponent's suit, you bid 3NT directly  to show a game forcing hand.
Opponent Partner Opponent You
    2H          double      pass      3NT <= no stopper, no major suit   
You: S8 HJ7 DQ1087 CAKJ973 or Jx Qx KJ864 AJ86

Note3: The Doubler without a stopper must reopen in his minor suit at level 4 with less than 16 hcp and in level 5 with more than 15 hcp, or bid his 5 cards major at level 4. In fact to play at 5 level the analysis must consider the immediate losers in opponent's suit.

LEB3) LEBENSOHL  AFTER  REVERSE

 In the follow hands the Opener bids a minor suit and then bids a higher ranking suit at the 2 level to show a hand type 54xx wiht 16-20 hcp. It is up to the responder to inquire his partner's hand to determine his strength - either 16-17 or 19-20 hcp and invite pd to pass in a partial score or to go to game.

Rule01: After Opener's reverse the only bid that is non forcing game is 2NT. In this case, the Opener must bid 3 if his hand is in the lower range of 16-17 hcp, else Opener bids anything else if he is in the higher range of 19-20 hcp. If the hand has 18 hcp, it is up to the Opener to choose the lower or higher range according to his felling and responder's initial bid.
Opener Opponent Responder Opponent
1C - 1 -
2 - 2NT <= Opener must bid 3 with 16-17
3 <= low range, responder can pass, or bid sign-off in 3, 3 or 3.

Rule02: Rebid of the responder's suit or support for any of the Opener's suit is a positive bid and game forcing, showing possible Slam interest.
Opener Opponent Responder Opponent
    1C           -                 1S                   -
    2H           -      (2/3/3/3) <= are all forcing game
(4/5) <= sign-off
Opener Opponent Responder Opponent
    1C              -                1H                     -
    2S              -  (3C/3D/3H/3S) <=forcing game
(4/5) <= sign-off

 OPPENING REVERSE HANDS WITH 5431 or 5422 WITH 16-20 hcp

Lets call a reverse hand one with 16-20 hcp, with 5-4-x-x distribution, where the 4 card suit is higher ranking than the 5 card suit. In this case, you open the bidding with the longer suit and bid the other suit at 2 level.
Examples
Hand 01     Opener Opponent Responder Opponent
SKQ108       1C         pass             1H             pass
H98             2S         pass              ?
DA5
CAKQJ5

Considerations: A second bid by Opener of 1S will indicated just a 12-15 hcp opening, but a bid in 2S shows a reverse hand of 16-20 hcp, with the addition that it shows 5 cards in the first suit (Clubs) and only 4 cards in the second suit (Spades).

?  the responder can have a minimum hand like 6-7 hcp, or can have a good enough hand to bid game or even a strong hand to bid Slam. So he needs to know in the range of 16-20 hcp, where is Opener's hand. Sometimes he just have enough points to bid game and the information of the range just is important to the opponents, so responder jumps directly to game. The important thing to recognize in this situation is that the captain is always the responder, so he decides the final contract.

To solve the problem of finding the range, wheter the lower range or the higher range, we use the Lebensohl rules in a reverse situation to determine the range mor precisely: 16-18(bad) hcp or 18(good)-20 hcp

The Lebensohl rules say that after responder's second bid of 2NT the Opener must bid 3 if he is in the lower range or anything else if he is in higher range. In fact, Opener's third bid in the higher range will show his 3 card suit with a 5-4-3-1 distribution or he will bid NT with a 5-4-2-2.

Example: SKQ108 H98 DA5 CAKQJ5, here the Opener have 19 points and 19 hcp. He is in the higher ranger, so he must bid 3NT because his distribution is 5-4-2-2.

Example: SKQ108 H98 DA5 CAKJ53, here the Opener have 18 points and a total of 17 HCP, so after the 2NT Lebensohl from the responder, he should bid 3C because he is in the lower range with his 17 hcp.

In all the follow examples let's make some assumptions about responder's hand:
Opener Opponent Responder Opponent
   1C             pass             1H     pass
   2S             pass              ?

Hypothesis1 = S743 HA1074 DQ104 C864 => bid 2NT undefined
If Opener bids 3C or 3NT you pass else you bid 4 sign-off is an option

Hypothesis2 = S7432 HA1074 DQ102 C84 => bid 2NT undefined
If Opener bids 3C responder signs off in 3 else signs off in 4S;

Hypothesis3 = S743 HKQ10654 D102 C84 => bid 2NT undefined
If Opener bids 3C responder signs off in 3H else signs off in 4H;

Hypothesis4 = S74 HA10742 DQ10984 C4 => bid 2NT undefined
If Opener bids 3C responder bids 3D a type of sign-off showing 5 Diamonds so Opener decide between Hearts or Diamonds at the 3 level. If Opener bids 3NT responder passes. If Opener bids his 3 card suit responder should bid game in this suit;

Hypothesis5 = SAJ74 HA1074  D102  C864 => bid 3S forcing
With 2 aces and 4 card support game is a must, even a Slam may be in consideration, so responder avoids bidding 4S directly, which would be conclusive, and gives the Opener room to elaborate on the distribution of his hand if he is in the high range. If he bids 3 Hearts the slam probably depends on a finesse, assuming a loser in Diamonds;

Hypothesis6 =  SA74 HQ1074 DK1042 C84 => bid 3NT sign-off
the responder's hand is good for game and there is no fit;

Hypothesis7 = S74 HAKJ54 DK2 C8642 => bid 3C GF
good chances for a Slam, responder must know more about Opener's hand. If Opener bids 3, a cue-bid, responder bids 3 if Opener bids 3 in sequence, responder bids 4, second control in Diamonds, so now in this cooperative cue-bids sequence, Opener and Responder can find a sure Slam contract ;

Hypothesis8 = S74 HAKJ542 DK42 C86 => bid 3H GF
the rebid shows a good suit, Opener can bid 3NT and responder bids 4 sign-off now, because only the support in Hearts from Open can lead to a Slam contract;

Hypothesis9 = S74 HAKJ54 DKJ984 C8 => bid 3D GF
bidding of another suit showing 5-4 or 5-5 in the reds, without goin through 2NT, is forcing game, and the problem of the hand is in the misfit, so if Opener bid 3NT or 4 or 5 responder can pass and if Opener bids 3 or 4 Opener must start a cue-bid or ask for aces in 4NT;

Hand 02   Opener Opponent Responder Opponent
SQ108         1D         pass         1S               pass
HAK108       2H         pass          ?
DAQJ95
C5

In this second hand the bidding of 2H shows a reverse hand with 16-20 hcp in a 5 cards Diamonds and 4 cards Hearts. The hand has 18 point and 16 hcp, so it is in the low range 16-18- .

Let's imagine responder's hand and make some suggestions for his second bid:

Hypothesis10 = SKJ743 HQ764 D84  C86 => bid 2NT undefined
If Opener bid 3C then responder sign-off in 3H because he has a minimum hand, else bid 4H;

Hypothesis11 = SAJ932 HQJ4 DK102 C84 => bid 3D forcing game
It is important to show honor support in the first suit bid, Opener can bid 3S to show his singleton in Clubs and now the responder assuming there is a loser in Clubs must choice between 4 or 6, depending on a finesse. The good alternative is to bid 5S asking for 2 honors in Spades to bid Slam.

Hypothesis12 = SJ9743  H1065  D102  CAQ6 => bid 2NT undefined
If Opener bids 3C (or 4) responder sign-off in 3H (or 4) else, if Opener bids 3 then responder bids 4, if Opener bid 3NT responder pass;

Hypothesis13= SAK974 H74 DK10 CAJ92 => bid natural 3C GF
If Opener bids 3S showing 3 card support responder must ask aces and using rkc if the answer is 5 showing 2 aces and Queen of Spades responder must upgrade his King Diamonds second and bid 7 if Opener has 1 King (Hearts);

Hypothesis14 = SAJ10974 H74 D102 CQ64 => bid 2NT undefined
If Opener bids 3 showing minimum then responder signs off in 3, else signs off in 4;

Hypothesis15 = SK974 H74 D102 CAJ982 => bid 3NT sign-off
better than trying to play in 5 if Opener has 3 cards in Clubs;

Hypothesis16 = SAQ1097 H74 D10 CQJ1064 => bid 3C forcing
If Open bids a black suit then responder must bid game in that suit, bidding seems to show a misfit and game is enough for this hand. If Opener bids 3ST responder can pass;

Hypothesis17 = SJ9754 HJ974 D10  CA92 => bid 4H sign-off;
There is no interest in detailing the hand for opponents, and responder knows the final contract;

Hypothesis18 = SK1097 H74 D2 CKJ10964 => bid 2NT undefined
If Opener bid 3C showing a minimum, pass is a good idea. If Opener bid 3 (3 card suit) you can bid 4 with a good chance in make many ruffs and 10 tricks. If Opener bid 4 you must bid 5. If Opener shows a 2=4=5=2 hand responder must accept 3NT for the final contract;

Conclusion, the Lebensohl convention is a tool for rationalizing your bidding, so must be used to improve a partnership.
There are others similar conventions: Rubensholh published by Jeff
Rubens in Bridge World may;1983 with similar ideas from Ira Rubin
Rupensolh is used in the Kaplam-Sheinwold system. Read more in https://www.bridgewebs.com/dba/Lebensohl_rubensohl.pdf
/ / / The End / / /  writed by Claudia Vargas -