Double = 13-15 balanced or any strong hand but note - with a takeout double of a major, pass planning to double on the next round; with a strong hand, double directly since 2D may be passed.
2M = Natural. Response in other major is cuebid, jump is natural.
2N = 16-18. Respond as to a 2NT opening bid.
3 of a minor = Natural.
3M = Strong (other major is a cuebid).
4 of a minor = 5+-5+ in suit bid and a major. (4/4 asks; 4/4=pass or correct).
AFTER: 2D - Pass - 2M/3M/4M:
Double = Takeout
All bids are natural - Even 2D - Pass - 2S - 3S is natural.
2D - Pass - 2M - Pass - Pass: Double = Takeout 2D - Double - 2M - Pass - Pass: Double = 18+
2D - Pass - 2H - Pass - 2S: Double = Takeout Responses to all these doubles are the same as after a double of a weak 2-bid. Lebensohl applies if you normally play it after (2M) - Double - Pass.
After: 2D - Pass - 2M:
4 of a minor = 5+-5+ that minor + a major.
2 NT =15-18 (respond as to a 2NT opening)
3M or 4M = Natural
After: 2D - Pass - 2H - Double - 2S:
Double = Penalty opposite takeout of hearts
3H = Natural, assuming that doubler is short in hearts
After: 2D - Pass - 2H - Pass - 2S - Pass - Pass:
Double = Takeout of spades
After: 2D - Double - 2 of a major which is pass or correct:
Double = Balanced, at least invitational values; if game force stopper only in bid major. Does not deny a 4-card major.
2S = Natural. 2NT = Forces 3C; signoff or game force with a minor.
3C = Stayman, game-forcing, continuations as after 2NT-3
3D or 3H = Transfers, at least invitational values.
3S = Both minors, game forcing.
3NT = 11-15 HCP, stopper in both majors.
4 of a minor = Strong invitation.
4M = Natural.
4NT = Blackwood.
After: 2D - Double - 2M - 2NT - Pass - 3C - Pass:
3H = clubs, game-forcing
3S = diamonds, game-forcing
3NT = balanced with stopper only in major not bid
AFTER: 2D - Double - Pass or Redouble (showing or tending to show diamonds):
2M = To play
2NT = Clubs (forces 3C with 13-15, then 3D = forcing club 1-suiter, others natural)
3C = Stayman, game-forcing, continuations as after 2NT - 3C. 3D or 3H = Transfers, at least invitational values.
3S = Game forcing, no diamond stopper.
3NT = 11-15 HCP, stoppers in both majors 4 of a minor = Strong invitation.
4M = Natural.
4NT = Blackwood.
After: 2D - Double - 3X:
Double = Penalty.
Suit = One round force.
4X = Cuebid After: 2D - Pass - Pass: As over a weak 2D.
(
geocities.com/drtodd13)