With dummy on your right, you should invariably lead up to the weak
suit. This is especially important when you hold no high cards in the
suit, for in this case the strength lies between your partner and the
dealer. By leading through the dealer’s hand you give your partner
the advantage of position; otherwise he may be forced to lead up to
the dealer’s strength.
In leading up to weakness, the general rule of leading the highest
card of a sequence should be followed. It is often good play, when
dummy holds no honour in the suit, to lead a card higher than dummy’s
best. This permits your partner, if the lead is not covered, to pass
the trick.
If dummy’s weakness is in the trump suit, your best play will often
be to lead trumps through the dealer’s strong hand, rather than to
lead up to the high cards in dummy. If you hold a guarded king and
dummy a guarded queen, do not be tempted to lead up to this honour.
It would be obviously wrong to lead up to a king if you hold the
ace. You must wait until this suit is led by the adversary or your
partner. Do not lead up to an ace in dummy if you hold the king. You
are reasonably sure to make a trick with this card if you wait until
the suit is led by the dealer or your partner. If you hold a sequence
headed by the queen or jack, little or no objection can be raised to
your leading up to an ace or king, and on each occasion the highest
card of the sequence should be led.
Should you lead a low card up to dummy’s strong suit, your lead would
indicate a singleton and a desire to “ruff.”