In a disturbed auction, bids of suits we have already shown are to play – often pre-emptive and based purely on Total Tricks.

New suit bids are forcing only if they are below game and partner's last call showed a suit. The logic is that, without a fit for partner's suit, you need power to introduce new suits into an auction. (But as we saw earlier, a takeout double followed by a new suit is a scramble.)

Natural rebids are never forcing.

WestNorthEastSouth
12
3
Forcing. 2 disturbed the auction and partner's last call showed a suit.

If instead you have a weaker hand wanting to compete in diamonds, and unwilling to make a takeout double, then you must be patient and pass – for now. For one thing, competing without any sign of a fit may well be the wrong thing to do. And for another, partner is still there and may yet re-open the bidding.

WestNorthEastSouth
3
3
Not forcing – partner has yet to call.
WestNorthEastSouth
3
dblpass3pass
3
Not forcing – West is scrambling with a spade-diamond two-suiter.
WestNorthEastSouth
1pass1NT3
3
Not forcing – partner's last call didn't show a suit.
WestNorthEastSouth
1pass1pass
1NT2passpass
2
Again not forcing: partner's last call (pass) did not show a suit.
WestNorthEastSouth
3dblpass
3
Not forcing. A disturbed takeout double is not considered to have shown a suit.
WestNorthEastSouth
2pass
3
Forcing. This coincides with the preference of most modern authors: why play anywhere but partner's pre-emptive suit unless you have a big hand?
WestNorthEastSouth
2NTpass
3
Forcing – partner's last call showed two suits!

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