The auction has ended and you are on lead. What now?
Someone has calculated that each time the defence leads a new suit it costs a half trick, i.e. one in two times it costs a trick. The opening lead is even more risky as you are leading blind and the only information to go on is the bidding. So it is imperative to find as safe a lead as possible. First, looking where partner has not bid.
Against suit contracts try and find leads from sequences, particularly in suits not bid by the opponents. In this case lead top of the sequence. Underlined in the following examples.
AK(Qxx), KQJ(xx), QJ10(xx), J109(xx). If you have an internal sequence lead the top of that sequence. KJ10(xx), Q109(xx). You wouldn’t normally lead the Q from AQJ as you will likely give away a trick to the K in declarer’s hand.
If you don’t hold any reasonable sequences then you need to try and find the less risky lead possible. Some leads to avoid if possible:
Don’t lead singleton Kings and Queens, (never if trumps) as declarer may finesse into your hand. Even think twice before leading singleton Jacks.
Leads of doubletons usually lead to disaster, as it often sets up declarer’s or dummy’s side suit. This is also often the case with singleton leads.
If you have to lead from a suit with an unsupported Ace, usually best to lead the Ace – it’s rather embarrassing when declarer wins with a singleton king!
In no-trump contracts it is a race between declarer and the defence to set up winning tricks. In this case you may be prepared to give away a trick with the lead in order to set up a suit. Good leads are as for the sequences above, but if you hold AQJx(x) the Q could be a good lead, particularly if you hold a likely outside entry. In this case you give declarer a trick with the King, but have the prospect of taking enough tricks in the suit plus other winner(s) to beat the contract.
If you do not hold a sequence then 4th best of your longest and strongest suit, as long as it is not one bid by declarer or dummy, is probably best, which allows partner to apply the rule of 13 to help with their decision making.
Things are a lot easier if partner has bid a suit. Against suit contracts singleton and top of doubleton leads of partner’s suit are good leads, as are tops of any sequences you may hold. Where you hold three or more cards to an honour it is a matter of partnership understanding whether to lead the honour or the lowest card. My preference is to lead the lowest card where declarer’s bidding has indicated the stronger hand and the honour where dummy’s bidding indicates the stronger values.
Against no trump contracts usually lead partner’s suit. An exception is where you hold a strong suit of your own, such as KQJ10x(x). Maybe also think twice about leading singletons (or even doubletons) of partners suit where declarer has bid no trumps strongly over partners bid.