First, Do No Harm

 Continuing with our hand from a recent Wydaho online pairs game:

♠ A 8 4
♥ J 10 8
♦ Q 10 8
♣ A Q 9 7

You are on lead against 1 NT; declarer opened 1 NT (15-17) after partner passed.

THE PRINCIPLE: Think of notrump contracts as a race: Can the defenders set up and cash their winning tricks before declarer crosses the finish line? 

We saw that a fourth-best club lead from this hand -- underleading the ace-queen -- has about a 70% chance of blowing a trick, giving declarer a trick she cannot get on her own. (To be precise, 71.2%, considering declarer could have 16 or 17 points.) Let's not give declarer a one-trick headstart 😝

We usually want a lead that will help establish our winning tricks, without giving away too much in the process. Against a notrump contract, finding and establishing five-card (or longer) suits is usually the winning strategy. If you don't have a five-card suit that looks worthwhile, maybe partner does; your two- and three-card holdings might be where partner has some length.

Where might partner have a long suit?  Note that if partner has a six-card (or longer) suit, she might well have opened a weak two or a higher preempt instead of passing. But we can still hope for a five-card suit in her hand. But which suit?

• Note that dummy did not transfer to a major over her partner's 1 NT; dummy does not have a five-card (or longer) major. 
• If dummy was 4-4 in the majors -- or even 4-3 -- she might have bid Stayman even with a very weak hand, planning to pass any response by opener

So if partner has a five-card suit, it is somewhat more likely to be a major suit because the opponents haven't peeped about the majors.

When leading against notrump, three-card honor sequences are always a good choice: king-queen-jack, queen-jack-ten, jack-ten-nine.  There is almost no danger of setting up a trick for declarer in those suits. Two-and-a-half honor sequences are almost as good -- king-queen-ten, queen-jack-nine, jack-ten-eight -- because there is only a very slight chance of giving up a trick. A suit with only two touching honors (and no supporting card one step below) is still a reasonable choice; the standard lead is low from honor-honor-fourth or fifth, but lead the top honor from honor-honor-third.

In this hand, then, the ♥ J is the standout lead. We hope to find partner with heart length, and not blow a trick on the opening lead. Our club tricks can wait patiently for somebody else to lead that suit.

Bonus Minute
When I started to play bridge, the standard advice for notrump leads was "fourth best from your longest and strongest." That was a long time ago; in those days it was dummy's job to go stand watch against dinosaur attacks. 😏  A lot has changed; much of what I learned back then turned out to be wrong (and not just the bridge bits, hmm).

If you are interested in more effective defense against notrump contracts, I highly recommend Winning Notrump Leads by David Bird and Taf Anthias. The authors created several hundred thousand computer-generated hands matching up with various notrump auctions, and did the double-dummy analyses to determine which leads were most effective in various situations. One key takeaway: Fourth-best from four is probably a waste of time. I specifically owe my first Regional Knockout Team win to the advice in that book. It is not an easy read, but well worth some patient effort by intermediate-to-advanced players; the book truly is a game-changer.

-- Ray
Better Bridge in 5 Minutes. Guaranteed! (or the next one is free)