Here is a diagnostic problem regarding use of the Stayman convention.  If you don’t use Stayman, after this you probably never will.  If you do use Stayman and don’t get it, you probably won’t ever again.  (Just kidding?)

S)  A 7
H)  Q 7 4
D)  K Q 8 5
C)  A J 7 3
 

Following your 1 NT opening, partner bids 2 clubs (Stayman asking if you have a four-card major).  In this particular case you do not have a four-card major, and you tell this to partner by bidding 2 diamonds.  The bidding continues:
 

You                     Partner
1 NT                       2 C
2 D                         3 H
 

After you denied a major, partner jumps to 3 hearts.  The challenge, if you choose to be challenged, is to figure out partner’s hand - distribution and strength.

 

ANS:  Partner’s heart call promises five of them.  So why did she employ Stayman when a direct heart bid (or transfer to hearts) would do?  There can be only one explanation: she has four spades and used Stayman to find a 4-4 spade fit or 5-4 heart fit.  Hence she has 4 spades, 5 hearts and 4 minors.  As to strength, the jump bid is game-forcing so she should have at least 10 points.  “Elementary” says Sherlock.
 

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