2/1 game forcing

2/1 game forcing (Two-over-one game forcing) is a bidding system in modern contract bridge structured around the following responses to a one-level opening bid:

1. a non-jump response in a new suit at the one-level is constructive and forcing for one round,
2. a non-jump response in a new suit at the two-level is forcing to game, and
3. a 1NT response to a major opening is forcing for one round and indicates insufficient values to immediately commit to game or bid a suit at the one-level.

The 2/1 game force does not apply to responses by a passed hand, or if there is an intervening call by an opponent. Other responses are per Standard American methods in accordance with partnership agreement.