When making an opening bid you must be planning your second bid, called a rebid.
If you open and your partner responds by bidding a new suit, you MUST bid again for one round.
If you open with 1NT (Balanced & 12-14 HCP), you MUST NOT rebid unless invited.
With an unbalanced hand the longest suit is opened first (length before strength).
The rebid is determined by a simple idea called the barrier. When making an opening bid, the opener must imagine a barrier at one level above the opening bid. ie.
1C has a barrier of 2C
1D has a barrier of 2D etc.
With fewer than 16 points, the Opener rebids her second suit as long as the bid is not above the barrier. When this is not possible the Opener rebids her opening suit. This is called a limit bid. Rebidding the opening suit usually promises a 6 card suit but 5 of good quality is acceptable.
The Responder, knowing the strength and shape of Opener’s hand can now continue bidding. A bid of 2NT by the Responder closes the bidding.
OPENER’S REBID WITH A STRONG HAND.
1. REBID A NEW SUIT ABOVE THE BARRIER. Any rebid over the barrier shows a strong hand of between 16 and 19 points. It also shows first suit bid longer than second. A rebid over the barrier could be the opening suit or a new suit.
1S - PASS - 2H - Pass
1S - 2D - PASS - 3D
The rebid at the 3 level is over the barrier of 2S showing a strong hand.
(Bridge Term - When the opener has rebid a senior suit to the opening suit this is called a Reverse)
2. JUMP SUPPORT PARTNER’S SUIT. This promises at least 4-card support.
3. JUMP REBID YOUR OPENING SUIT. This promises at least 6-cards.
4. JUMP IN A NEW SUIT - forcing to game.
Strong Balanced Hands
With a strong balanced hand and no 5 card Major, open with your lowest 4 card Major suit. If no Major fit is found from the response a rebid of NT will describe the strength:
15 - 16 : REBID NT at the lowest level
17 - 18 : REBID NT with a jump
19 : REBID 3NT
When partner makes a rebid ‘Above the Barrier’ assume 6 losers. When partner‘s rebid is a limit bid, assume 7 losers.