Before we discuss conventions, let's discuss the situation!

To me, it is a crime to watch the opponents open one notrump and bid unimpeded. Your opponents are great bidders after their one notrump opening. They are so expert that I'll bet they use asking bids and relays. Yes, even your lesser opponents play that 2 asks, and that 2♦ and 2♥ relay to the next suit. The science of bidding after a one-notrump opening is quite accurate and all of your opponents are comfortable with the methods.

They are not comfortable, however, with interference. Not only do you take away their Stayman and Jacoby, but you put them into uncomfortable territory. Even experts with well-oiled mechanisms (lebensohl, negative doubles) have a difficult time coping with interference.

If your partner opened one notrump (15-17) and you held, say,

your plan would be easy. You'd transfer to two hearts and then invite with two notrump.

But, if RHO overcalled one notrump with two spades, would you be happy?

What if the overcall was two diamonds, showing diamonds and a major? What would your bids mean? Can you play from the right side? What would you bid? (For more on this, see: Notrump Interference -- intermediate version OR advanced version).

It's quite obvious how the interference makes notrump auctions a challenge. Given that, we should go out of our way (way out!) to interfere. Don't worry about ``having your values,'' -- your goal is just to disturb, it's not to convey your hand to partner so that he can bid a game or double them.

In balancing seat (after 1NT  P  P ...), I can't stand to pass. I go out of my way to balance with almost any hand that contains a 6+ card suit, or at least 5-4 in any 2 suits. HCP don't matter (what you don't have, your partner will).

Once you decide to interfere, I feel strongly that the best method is DONT. There are many methods to choose from (so many, that you can start an alphabet song such as: A if for ASTRO, B is for BROZEL, C is for CAPPELLETTI, D is for DONT...)

DONT allows you to show all one- and two-suiters at the two level. Your goal should be safety. The other methods put more emphasis on penalty doubles, and or getting to majors.

Opponents open strong 1NT:

In direct or balancing seat our bids mean:

Double = One-suited hand (requests 2 from partner)

2 = 2 suits, + higher

2♦ = 2 suits, ♦ + higher

2♥ = 2 suits, ♥ + higher

2♠ = Natural

(Against weak notrumps, I recommend some other system that employs double to show a good hand.)

Penalty doubles of strong notrumps are, in my opinion, horrible. Yes, horrible. It makes it easy for them to run out (often to two-of-a-minor, normally unreachable), and when they do sit, it's usually ``impossible'' to make an opening lead and defend (declarer's advantage).

Getting to the higher-scoring major is also not my priority; again, it's a matter of percentages. In the long run it's better to get all one- and two-suiters into play and not worry about how big your plus score is; the focus is on how low your minus score is! Get in, get out, and you'll be a winner.

Usually we try to have at least 5-4 in the 2 suits -- vulnerability is relevant, as is "position" (Direct seat is "never" 4-4).

Don't worry about game!

Balance with "few HCP" but with shape!