Rosenkranz Double & Redouble Convention

The Rosenkranz double and redouble convention is used to respond to partner's overcall when right-hand opponent has made a forcing response to his partner's opening bid (a bid in a new suit or a negative double)

Examples

1. Bidding W 1 N 1 E 1 S ?

South 9 2 K J 10 10 8 5 3 A 9 8 4

Support double (6+ HCP  3+ ) 1 round Forcing bid showing a three-card trump support, with the ace, the king or the queen

2. Bidding W 1 N 1 E 1 S ?

South 9 2 J 10 6 K 8 5 3 A 9 8 4

2 (6-9 HCP  3+ ) limiting Non forcing bid showing a three-card trump support, without the ace, the king or the queen

3. Bidding W 1 N 1 E x S ?

South 9 2 K J 10 10 8 5 3 A 9 8 4

Support redouble (6+ HCP  3+ ) 1 round Forcing bid showing a three-card trump support, with the ace, the king or the queen

One other thing to talk over with partner: Do you play Rosenkranz when RHO bids NT ?

Copyright 1999 BridgePassion.Com

Another use suggested by Mike Lawrence

Rosenkranz Doubles used when you are a passed hand and responding to partner's overcall.

All these factors must be in place. Your LHO opens, RHO bids a new suit and partner overcalls at the 1 or 2 level. LHO raises partner's suit or makes a Support Double. (If they use a Support Double you can use redouble to show an honor raise). You have a single raise with 3 card support with or without an honor.

Here are some examples:

1

W	N	E	S
	1	Pass	1
1	2	?

2

W	N	E	S
	1	Pass	1
2	2	?

3

W	N	E	S
	1	Pass	2
2	3	?

4

W	N	E	S
	1	Pass	1
2	Dbl*	?

*Support Double