Opening lead

The opening lead is the first card played in the playing phase of a contract bridge deal. The defender sitting to the left (LHO) of the declarer is the one who makes the opening lead. Since it is the only card played while dummy's cards are still concealed, it can be critical for the outcome of the deal. Making the best opening lead is a combination of selecting the best suit and then the best card within that suit.

Considerations are:

N



S

North and South have reached a contract of 4♥, which has some possibilities. At first glance the declarer seems to be losing a spade, a heart, maybe a diamond if the finesse fails and a club or maybe more. However, if the opening lead is the ♥2 (a safe lead) Declarer will find it much easier to make the contract because he will have time to set up the diamond suit. The ♠4 lead (an aggressive lead) will make his job more difficult.

Partnerships may choose their own method of "carding". The following is considered fairly standard (mainly Klinger 1994 ):

Ambiguities can arise from this standard method, thus:

To overcome these problems various conventions have been devised:

When West leads the ♠K East may be confused as to the nature of his holding. If he is leading from ♠KQ East will want to encourage, but if leading from ♠AK East will want to discourage. Rusinow leads recommend leading the second of touching honours and the above confusion is largely eliminated. Rusinow leads are now considered a standard part of the Roman Club system.

The leader might have J1094 or KJ104. The convention proposes that the opening lead be the Jack from the first sequence and the 10 from the second in order to better inform his partner about the nature of his holding.

...
Wikipedia