It's one thing to learn how to play Michaels Bids and Unusual Notrump. The next step is to learn how to defend against these bids when your opponents use them. When they make such a 2-suited bid, the first thing we need to know is "What 2 suits are they showing?" 

In some cases we know exactly the 2 suits, in other cases, we are not sure.

For example:

West North  1 2NT

North's Unusual 2NT bid promises the 2 lowest unbid suits -- so we know he has both +

Or,

est North  1  2

We know that for his Michaels Bid, North has both +

However, if the auction begins:

West North  1 2

North is showing + EITHER MINOR.  We are sure of only 1 suit. The other is unknown.

In preparing our defense, it is important to distinguish between these 2 situations. Either we know for sure both suits, or sometimes we know only one suit. Now, let's formulate our simple defense (although it does require work and memory).

In all cases, we can define a DOUBLE as "penalty oriented."  It means we are interested in penalizing the opponents. All future doubles by either player in our partnership are for penalty.

In all cases, we can say that if we PASS, we likely don't have a good hand.  I'd say about 0-8 depending on the level/situation.

What about other actions?

Raising Partner's Suit - In all cases, raising partner's suit is natural.  Raising to the minimum level is about 7-10 points.  Raising to game shows a little more. 

Examples:

West	North	East
1	2NT	3

West	North	East
1	2	3

In both cases, East is showing about 7-10 and support (to raise the major, he has at least 3-card support; to raise the minor, at least 4-card support).

 
Bidding the Opponent's Suit - If the opponents have only one known suit, then bidding that suit is artificial and shows at least a limit raise for our partner.

Examples:

West	North	East
1	2	2

West	North	East
1	2	3

In both cases, East is bidding the opponent's one known suit. He is saying, "Partner, I have support for you (at least 3-card support) and at least a limit raise. I have 10+ in support -- I might be just inviting you to go to game with a maximum. On the other hand, I might be looking for slam--you will find out later."

So, East might have: 5 4
A Q 2
A 8 7 5 3
10 3 2
 in the first example, and Q 7 6
7
A K 7 6
K J 7 6 4
 in the second example.  In neither case is East saying anything about the opponent's suit--he may or may not have the suit controlled.

Note that there are 2 ways to raise opener.  One is by simply raising (bidding his suit). The other, which is the stronger way, is to artificially bid the opponent's known suit (showing invitational to game or better).

What if the opponent's have TWO known suits?  Now, the responder will have 2 suits to cue-bid. For example:

West	North
1	2NT

or

West	North
1	2

In these cases, North has TWO known suits. In the first case he has specifically +.

In the second case he has specifically + .

East now has many options. He can raise partner naturally (as discussed above). He can also cue-bid in either of 2 different suits!  What do these cue-bids mean?  One of them should be the limit raise or better (as discussed above). The other cue-bid means something entirely different, which I will get to in a moment.

First, we have to decide which cue-bid is the limit raise or better. There are several different ways to do this and all partnerships must agree.  I think the best is to say that the "second" cue-bid is the limit raise or better. By "second," I mean the higher of the 2 bids the responder can make.  For example, if it starts 1-2NT, the two possible cue-bids are 3 and 3. The highest is 3, so that would indicate the limit-raise or better.   It is important to agree on which cue-bid is which. There are 2 other ways which I won't go into here, but make sure you pick one and agree.

So, what does the "other" cue-bid mean?  It says that the responder has the "4th" suit: Not partner's suit and not one of the opponents suits. It also says he has at least an invitation to game.  For example:

West	North	East
1	2NT	3

We have agreed that 3 (the highest cue-bid) shows the limit or better raise of partner's   suit. Therefore, 3 is the "other" cue-bid. In this case it shows the "4th suit."  What is that suit?  West has .  North has +. So, East is saying he has spades (at least 5) and at least game interest.  If he had spades and a weaker hand, he would just bid 3. A bid of 3 by East would be Non-Forcing.  In that case, it must be a pretty good suit (like a weak two-bid) -- at least 6 cards. East wouldn't bid 3 just because he happened to have 8 HCP and king-empty fifth of spades.

REVIEWUsing the definitions above, what does East have for each action shown?

West	NORTH	EAST	EAST IS SHOWING....
1	2	DBL	Penalty Interest
1	2	2	Diamonds, not forcing
1	2	2	Diamonds, Game Interest
1	2	2	Club raise, Limit or better
1	2	2	Clubs, Game Interest
1	2NT	3	Hearts, Limit or better
1	2	3	Spades, Limit or better
1	2	3	Spades, 7-10
1	2NT	3	Like a weak 2-bid in

This is far from a complete treatise on the subject, but should be good enough to get any partnership started. It is not easy on the memory and requires work and study.

I don't like teaching this topic, because the natural reaction is to say: "This is too complicated."  I don't like complicated. However, your opponents will use Michaels and Unusual 2NT bids. If you don't want to study/learn this defense, then you will be at a huge disadvantage on these auctions.