This convention allows you to bid 2NT to show the high point count while not denying a 5-card major.
For example, with 20 points and 5 spades, an opening bid of 1 spade may be passed out with partner holding 5 points, while the opposition are more likely to come in with a lead-directing bid. Partner is more likely to respond if you open 2NT.
| Responses to 2NT opening bid = | 3C, asking partner for a 4 or 5 card major, |
| otherwise transfers, weak take-out etc. as normal | |
| Opener rebids - |
3D = I do not have a 5 card major but I do have a 4 card major |
| 3H,3S = Yes I have this 5 card major | |
| 3NT = I have neither a 4 or 5 card major |
In response to 3H or 3S partner can now pass the major suit if very weak, raise the major, or bid 3NT etc. If opener shows a 4 card major by bidding 3D, and responder also has a 4 card major, responder bids the other major to the one he actuallyholds e.g. 3S when holding four hearts. Now, if opener also holds four hearts he can bid 4H and plays the hand as if it was a transfer with the benefit of the lead coming round to him. If responder has two 4-card majors, and therefore a singleton or doubleton, he can bid 4D to show both and opener now bids 4 of his major knowing that partner also has 4 of this suit.