If you have a 7-card suit, at least one outside trick, and 7 to 11 points, you can do what is called a preemptive bid by bidding 3 of the long suit (e.g. 3 Diamonds). An outside trick means that you would expect to make a trick 'outside' your long suit.

Example

Here you have a king, a queen, 2 jacks, and 3 doubletons, giving you 10 points.

You also have a 7-card suit, diamonds, and 1 outside trick, the king of hearts, so you have all the requirements for a preemptive bid of 3 Diamonds.

Notes

• In a doubleton the king of hearts has a fair chance of making, so it counts as an outside trick. However, the jack of clubs would probably not make, so that would not count as an outside trick.
• The typical response of your partner to a preemptive bid is 'no bid'. If your partner bids, he or she should consider the 'bidding targets' for assessing the points needed to bid higher.