Dutch Doubleton Opening

Dutch Doubleton is a system that is derived from Polish Club. It is very popular in Holland.

1 shows one of three hands:

• 11+ unbalanced 5+ suit in clubs, or 4441 (with 4 clubs)
• 12-14 balanced, no 5 card diamond suit
• 18-20 balanced (any 5332 possible)

1 shows one of two hands:

• 5+ diamonds (not 18-20) balanced
• 4 diamonds unbalanced. 4441 or 4 diamonds and 5 clubs.

1/1 - Standard 5 card opening

1NT - 15-17 balanced

2 shows one of three hands:

• weak 2 in diamonds. five/six card+, 5-10 HCP
• 23+ 5,3,3,2 which includes a 5 card major
• Big hand. unbalanced game forcing (with one exception)

2 shows one of two hands:

• Multi: 5-10 HCP. weak 2 in a major
• 21-22 5,3,3,2 which includes a 5 card major

2/2 - Muiderberg, 5-10 HCP with a 5 card major and a 4 card minor

2NT - 5 or more clubs and 5 or more diamonds, 5-10 HCP

3 - 3-9 HCP with 6+ clubs (not AKQ+)

3/3/3 - 3-9 HCP with 7+ (not AKQ+)

3NT - 3-9 HCP, 7 or 8 card suit in clubs or diamonds. (not AKQ+)

4/4 - Namyats, 8 playing tricks in a major, AKQ 7th or 8th.

4/4 - 3-10 HCP, 7 or 8 card+ suit, also could be AKQ 7th, purely preemptive

4NT - Acol 4NT opening, asks for aces

5/5 - 8 or 9+ card suit, purely preemptive