• SYSTEM IS OFF after almost any intervention (e.g. an overcall or a penalty double), but it's still on if the opponents make a double that is known by both Finn and David to be merely part of a system of overcalls (e.g. Meckwell). If in doubt, don't make the latter assumption.
  • DEFENDING AGAINST CONTINUATIONS: if the meaning of an opponent's continuation isn't known, for simplicity it should be assumed to be the same as ours.

  • PassTo play. If the opponents compete in a suit, a next-round double from this hand is competitive and for takeout.
    RedoubleWants to double the opponents for penalties.
    2CStayman, promising either (a) a four-card major, or (b) a long minor suit and slam interest.
    2Dtransfer to 2H
    2Htransfer to 2S
    2Stransfer to the minors
    2NTquantitative with 9 points or a good 8, inviting 3NT
    2NT after overcallto play, not invitational. There's no longer any invitational sequence available after the opposition have intervened over our 1NT opening. You'll have to take a view and either bid 2NT or 3NT for yourself, either of which partner will pass.
    3C after an intervening Unusual 2NT for the minorsStaymanic with game-going values, denying a five-card major.
    3 of a suitgame-forcing splinter, promising a four-card major and opening hand strength. Unlocks Blackwood. A hand that wants to splinter if 3-1 in the majors should go via 1NT-2S.
    3NTto play
    Cue-bid after overcallasking for a stop for 3NT
    New suit after interventionNatural and non-forcing, to play, all conventions off. Opener is expected usually to pass. If instead they bid again after 1NT (2H) 2S, for instance, this is similar to breaking a transfer or raising partner's weak takeout. It's a gamble, obviously, but sometimes it strikes gold because partner will have been holding invitational values and the overcall deprived your side of an invitational sequence. It shows an encouraging maximum and if it's a new suit, promises a good five-card suit.
    Jump shift after interventionnatural, game-forcing
    DoubleTake-out if below 4S. Uniquely, to double and then keep bidding when/if partner takes it out is game-forcing (and shows at least a five-card suit), which isn't what the sequence shows after other opening bids. The reason is that an immediate bid (instead of double) would have been non-forcing and to play, so by corollary making a takeout double and then bidding on must be strong and forcing. This will still be true even if partner subsequently doubles (penalties) the opponents after they've kept up their intervention... if responder had a weak hand that couldn't stand to hear opener make a penalty double, then it shouldn't have made a takeout double in the first place and should have either passed or bid a suit.
    4C, 4D, 4H, 4STransfer to next suit. Super-accepts are banned at the four level.
    4NTquantitative invitation to 6NT
    5 of a minorto play
    5 of a major"pick a slam", 5440 shape with a void in the bid suit.
    5NTquantitative invitation to 7NT
    any slamTo play, showing a no-loser trump suit at the six level. Not a transfer.


  • Two-suited bids are available, a bit like our defence to a Precision 1C, but the difference is that there's less urgency and more danger involved in getting into the auction because a 1NT opening is very informative immediately. The system stays the same when defending against an opening 1NT of any strength, except that double is for the majors against a strong no-trump and for penalties against weak or super-weak options.

  • Any bid in the pass-out seatA king weaker than when bid directly, EXCEPT for double.
    Doublethe majors
    Double from a non-passed hand against a known weak or super-weak no-trump, i.e. an average point count below 15 pointsStrong, for penalties. Promises at least two points more than the average point count for an opening 1NT in the opponents' system. IMPORTANT: not shaded by three points in the protective seat, because responder's pass could still be strong-ish and usually isn't a disaster area. However this is a unique situation and "transfer a king" still applies in all other protective positions.
    Suit (any level)Natural
    minimum club bidclubs and a major
    minimum diamond biddiamonds and a major
    No-trumps (any level)the minors
    Jump to 3NTto play, with a long minor
    Copyright 2015 Finn Clark.