An opening two of a minor shows a hand with at least six cards in the bid minor and opening values – a nominal minimum strength of 12 points. There may be four cards in the other minor (but with five in the other minor, 2NT would be a better choice of opening).

In first and second hand, there won't be a four-card major side-suit. In third position, the long minor may be only five cards and now it is acceptable to suppress a four-card major if you judge the pre-emptive effect of the two-level opening to be more valuable.

All responses are systemic. 2NT is natural and unlimited, but will frequently be the first move on any good fitting hand with no splinter. It allows opener to define his hand further (most particularly, to show any shortage), and it means that direct jump raises can all be pre-emptive. Responder can also introduce a new five-card suit, unlimited and showing at least invitational values. Continuations are systemic, but with an emphasis on finding 3NT.

WestNorthEastSouth
AK722pass
9765?
A4
A86
Bid 2NT, natural and not limiting, so forcing. 2NT opposite an opening two of a minor effectively says that we will play in the minor or in no-trumps, since a new suit by either partner will be an impossibility and so set the minor. On this hand, if partner can splinter in hearts, slam could be good even opposite a minimum e.g. Q62KQ75KJ9543.
WestNorthEastSouth
AK82pass2pass
KJ3?
4
QJ10942
Bid 3NT. Both majors are well stopped, particularly if you are declarer, and you have enough extra values to make game a good prospect. It's possible that partner has a five-card major, but he will know you have good fragments in both majors, and it is highly unlikely that you will miss six if he passes 3NT.

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