When do you use Negative Doubles?
There is only one auction where they can occur:
Opener: 1 anything
Overcaller: any SUIT overcall
Responder: X Double
How many points do you need to be holding to bid a XDouble as a responder?
Depends on what points you are holding:
1 level: 6+
2 level: 9+
What suits does a Negative Double Show?
The unbid suits, with the focus on majors. There are two auctions where the XDouble comes with a guarantee: whenever the overcall is 1 diamonds (says I have 4+ in both majors) or 1 hearts (says I have 4+ in one major)
If the overcall is 1NT, can you respond with XDouble?
No, only overcalls that are in suits can be responded to with XDouble.
Should you XDouble all overcalls?
No. Don’t forget the basics. A 1NT bid shows about 7-10 balanced hand with their suit stopped. Bid this unless you have a four card unbid major.
