If you have:
No need to have 3 or 4 cards in all other suits e.g. can be a:
1. Single suited hand too strong for a simple overcall
If partner answers in the wrong major, change it. It is a very strong overcall.
2. A balanced hand too strong for a 1NT overcall (18 HCPs)
If partner bid 1C/1D, and opponent overcalls with a suit bid (e.g. 1H) cannot overcall (1S) with 4 cards in suit, otherwise use (X). Promises 6+ points at 1 level and 8+ at 2 level
If partner bids 1C and opponent bids 1D, DBL means 4 hearts and 4 spades
The support double is a double by opener to show 3-card support for responder's suit.
NOTE: Do not use DBL if opponents have not bid, as this is not allowed and you can be penalised if the director is called
When to Play Support Doubles:
And now, some more fine print when support doubles might NOT apply:
This is a DOUBLE of opponents artificial bid. It means that is my suit and I was going to bid that. e.g slam bidding, 2C stayman and transfers, 2D after a strong 2C opening.
In most cases artificial bids are taken out, so usually partner does not need to bid. However if partner has points and that suit they can then bid it. Or they can bid a suit of their own.
If you end up defending the double is then LEAD DIRECTING
This is used above a certain level (e.g 3) by partner agreement, or over a 1NT bid.
Only use this when you know the declarer will be defeated.
RULE OF 9 - add the number of trumps in your hand plus the number of the trump bid, if it equals 9 the DOUBLE
NOTE: If partner has been doubled and RHO opponent has unexpectedly passed, you can REDOUBLE (XX) to allow the bidding to continue and partner to bid again.
You must respond (rarely can you leave it - needs 6 cards in the bid suit - 3 sure trump tricks and at last one non-trump trick) so bid your best alternate suit. Always give preference to a 4 card major suit even if have a 5 card suit in a minor. Can add TP as you know that you have a fit.
Yes if at all possible, bend the rules slightly - stretch to bid
If bids a suit but has not jumped - still has only 8 HCPs, so
Shows a stopper and 8-10 HCPs