Opponents interfere over our 1NT opening

After a Penalty DBL

• RDBL: 5+ in a minor, weak. Partner must bid 2C.
• 2C (Stayman): Maybe 4+4+ in majors in a weak hand. Partner has only 3 possible responses.
• 2D/H: Transfers
• Pass: Weak, no 5+ suit, no 4-4 in majors. Partner may RDBL to initiate a scramble or bid a suit with 5+ cards.
• All other bids are un-changed

After a Non-penalty DBL the system stays unchanged. RDBL is for business (usually less than game values).

After a level-2 overcall showing explicitly only 1 suit (either a 1-suiter or a 2-suiter with an un-known second suit)

• New suit at level 2: competitive, non forcing
• DBL: Negative (Stayman)
• Pass over an artificial overcall followed by DBL: Business
• Cue-bid at level 2 (If possible, i.e. after a transfer intervention): Take-out, no indication about stoppers. May hide a limit club 1-suiter, but typically has values for 2NT.
• 3NT: With stopper
• 2NT: Lebensohl relay to 3C. After the relay:
  • Pass: competitive in clubs
  • New suit lower than opponent’s bid: competitive
  • New suit higher than opponent’s bid: game+ with stopper
  • Cue-bid: Take-out without stopper
  • 3NT: Without stopper
• Other bids over 2S
  • 3C/D: Transfer to diamonds/hearts
  • 3H: Singleton spade, 4 hearts
  • 3S: Singleton spade, 3 hearts
• Other bids over 2H
  • 3C: Transfer to diamonds
  • 3D: Singleton heart, 3 or 4 spades
  • 3H: 5 spades without heart stopper
  • 3S: 5 spades with heart stopper
• Other bids over 2D
  • 3C: Stayman
  • 3D/H: Transfer to hearts/spades
• Other bids over 2C
  • 3C/D/H: Transfer to hearts/spades
• 4C/D: 5+5+ in the suit and another (usually major) suit
• 4H/S cuebid: 5+5+ in minors
• 4H/S otherwise: To play

After a 2-suited overcall showing explicitly both suits

• New suit: Competitive
• DBL: Business if overcall is natural (Negative otherwise)
• 2NT: Invitational
• Lower cue-bid: Shows the lower of the other 2 suits
• Higher cue-bid: Shows the higher of the other 2 suits

After 2NT with a 2-suiter (usually the minors)

• Pass: The equivalent of a Negative DBL or a Competitive bid or a Pass
• DBL: business interest and also initiates stopper investigation
• All other bids are as above

After a Natural Overcall at level 3

• DBL: Negative
• New suit: game forcing
• 3NT: sign off
• Any jump at level 4 retains its original meaning (4D/H Texas or 4S/NT QST)

After a DBL of our Stayman 2C

• 2NT: 4-4 in the majors, club stopper, no indication for min/max
• 3C: 4-4 in the majors, no club stopper. Responder usually bids his major suit, but can bid 3D to still make opener play the hand!
• 2D/H/S: Unchanged, but with club stopper
• Pass: Any other hand without club stopper. If next opponent passes, responder bids RDBL. Opener’s responses:
  • 2D: No 4-card major suit
  • 2H: 4+ spades. Responder can bid 3H to still make opener play the hand.
  • 2S: 4+ hearts. Responder can bid 3S to still make opener play the hand.
• RDBL: Let’s play 2 clubs!

After an overcall of our Stayman 2C

• DBL: Business
• 2H/S: 4 cards
• Cue-bid 3D: 4+ cards in both majors
• 3C/D: Good 5+ suit
• Pass: Otherwise. If next opponent passes, responder bids:
  • DBL: Business
  • 2H/S: Competitive
  • 3H/S over 2D: Smolen
  • Cue-bid: Asks for stopper
  • 3C/D: Natural, forcing
  • 2/3NT: Limit

After a DBL of our 2D/H bid (showing the suit)

• Pass: Only 2 cards in partner's suit
• 2H/S: Sign-off, prefers to play the hand
• 2NT: Limit, without stopper
• New suit: Competitive
• Cuebid: Short in the suit, limit or more
• 3H/S: Limit, prefers to play the hand
• Jump cuebid: Void, slam invitation
• RDBL: Relay – opener must accept the transfer. Follows:
• 2NT: Limit, with stopper
• Cuebid: Semi-stopper, looking to play 3NT
• Jump cuebid: Singleton, slam invitation
• 3H/S: Limit, shows at least 2 quick loosers in opponents' suit!
• New suit: Forcing
• RDBL: 3+ fit without stopper
• 2H/S: To play
• Others: Natural game tries
• 2H/S: 3+ fit with heart stopper
• Other: Max, 4+ fit

After a DBL of our 2S/3C transfer bid (showing the suit)

• Pass: Only 2 cards in partner's suit
• 2NT: Trying for 3NT
• 3C/D: Prefers to play
• RDBL: Otherwise
• RDBL: 3+ fit without topper
• 3C: 3+ fit with stopper
• Other: Max, 4+ fit

After an overcall of our transfer bid

• Pass: The usual bid. After opponent’s pass follows:
• DBL: Negative
• New suit: Competitive
• Accept own transfer: Competitive
• NT: Limit
• Cue-bid: Take-out
• Jump shift: 5+5+, game values
• DBL: Negative
• Other: Fit