Bridge Chestnut 6 - "A change of suit by an unpassed responder is forcing"

This chestnut is by partnership agreement. It is meant to apply to uncontested auctions not starting with 1NT or a pre-empt. When our auctions start with 1NT or a pre-empt, our response have different meanings.

11
1NT2
?

Here is a typical auction where opener must keep bidding. Responder’s hand is unlimited.

On the contrary:-

11NT
12
?

This 2D bid "begs to be dropped". Responder has shown less than 10 HCP, at least 6 diamonds and hopeless holdings in opener's black suits.

 

1(2) 2

Whether 2D is forcing depends on partnership agreement. Here, the opponents have overcalled at the two level showing a goodish hand. Many pairs play 2 here as a Negative Free Bid showing about 8 – 11 HCP and a 5 card suit, not forcing.

Go to Chestnut 7 - A new suit at the three level is forcing