Negative Doubles

Board 5
North Deals
N-S Vul
10
K 9 7 4
K J 9 8 7 2
A 4
J 8 7 6 5
A J 5 3
J 8 6 3
N
WE
S
A K Q 4 3
Q
Q 10 6 5
K 5 2
9 2
10 8 6 2
A 4 3
Q 10 9 7
WestNorthEastSouth
 1112Dbl3
34Pass4All pass
  1. N opens 1
  2. E overcalls 1
  3. S uses a negative double showing
  4. W has an easy competitive raise. A grateful E happily bids to game.
4 by East