Developments after weak 3 opening

Since a weak-3 opening bid already shows a 7-card suit, a new suit should not normally be bid without at least game interest. Bidding a new suit over a weak-3 opening should therefore be game forcing, usually with an attempt in finding a major fit.

Bidding sequence	Meaning	Remark
3A > 3NT 3m > 5m 3M > 4M	To play
3m > 3B	usually 6 cards, F1	4C response after F1 is suit
3H > 3S	usually 6 cards (0 heart), F1	4C response after F1 is suit
3A > 4C	Gerber
3M > 4D	usually 6 cards, F1
3S > 4H	usually 6 cards, F1	Choose 4H/4S