One club bid can be either an artificial bid promising between three and five honor tricks or a normal club bid. In the latter case the clubs are re-bid on the second round. Other one bids showed that the opening was about a minimum in honor strength. Two bids are strong and forcing.

A method of slam exploration after a raise to four no trump. After the bidding: 1NT - P - 4NT, opener declines the invitation by passing if he has a minimum. With an average hand in terms of point count (i.e., 17 points using a standard 16 - 18 no trump) he bids five of his lowest ranking biddable suit. Responder acts accordingly, and may jump to the six level in another suit without excluding other contracts. A five no trump rebid would deny a biddable suit.

With a minimum hand, the opener jumps to the six level in his lowest ranking biddable suit in similar fashion.

The convention can be used in the same way after any natural jump from two no trump to four no trump.