The system of honor card leads versus notrump commonly in use today have several deficiencies. The following suggestions go a long way toward remedying those shortcomings, providing the defenders with ample opportunity to send and receive the information needed to conduct a successful defense.
Traditionally, the lead of the ace against notrump shows a powerful holding in the suit and asks partner to unblock his king, queen, or jack; otherwise he gives count. Thus, the ace would be led from AQJT(x), AKJT(x), or AKQT(x). The opening leader might also judge to lead the ace from the above honor holdings when he lacks the ten but has a five card suit, and almost certainly when he has a six card suit.
It is easy to see that it is unnecessary to require partner to unblock the king when the ace is led. Unless the opening leader strongly suspects that a singleton king is outstanding or has a certain entry in another suit, he will lead a lower honor from AQJTx. This will enable him to maintain communication with his partner when an opponent has the king. If partner has the doubleton king, he will unblock it at trick one and return the suit. With three or more cards headed by the king he will encourage. The defenders should have little trouble running the suit.
There is one other important holding in addition to AKJTx and AKQTx where we would like to see partner unblock an honor for us. That is KQT9x. The modern treatment is to lead the queen to "demand the play of the jack". This creates a possible problem when partner has the ace without the jack, places declarer with the king, and thinks that we need to win tricks quickly in another suit. (See RATS, April 1974 Bridge World).
Another problem occurs when partner has neither the ace nor jack, assumes we are leading from QJ, and plays an attitude signal based on his failure to hold the king or ten. For example,
KQT95 (a) 82
If using standard attitude signals, on our lead of the queen, partner will play the deuce from both 82 and 862, leaving us with little idea whether to continue with the queen or switch to anther suit.
What we want is for partner to unblock the jack or else give count. But wait! That is exactly what we want partner to do when we have AKJTx or AKQTx. Note that the only high honor in common between AKQTx, AKJTx, and KQT9x is the KING. Thus, if we lead the king from each of those holdings, partner will play the card that gives us the information we need. Additionally, if he does hold the ace, he will know what we have and play accordingly (normally winning the ace and returning the suit). Therefore, it is superior to use the king as our "strong" lead, asking for the unblock of the queen or jack, or else count.
The king is the "standard" lead from AKTx. Partner would encourage with the queen, and we can continue the suit. Unfortunately, since the king is also the standard lead from KQTx or KQx, partner would also encourage when holding the jack, giving us a problem. Having reassigned our strong honor lead from the ace to the king, we have freed the ace to show the king and ask for an attitude signal. The removal of the ambiguous king lead puts us in better position to judge how to continue successfully should we have AKTx.
From AKxxx we would nearly always lead a low card on opening lead. If partner has the defender's entry, it is vital for him to have a card to lead to our established suit when he started with a doubleton. However, should we hold AKxx, it is not necessary to lead low at trick one in order to maintain communication. If we lead the ace, the appearance of dummy and partner's signal can guide us to continue with a low card at trick two if that seems appropriate.
Leading low at trick one does gain when partner started with QJx, and either declarer or dummy has four cards in the suit, and it is better if partner has Qx or Jx. Additionally, the low lead gains when dummy has the queen (1/3), partner the jack (1/3), and declarer or dummy the ten (2/3) for a combined chance of 2/27 or about 7%. However, dummy needs at least three cards in the suit for the low lead to gain, further reducing the times when leading low works better.
Leading high gains when either declarer or dummy has the doubleton queen and partner the jack. It also gains if partner has the ten and an opponent the QJ doubleton or if partner has JTx and declarer the queen. Best of all, partner could have five of the suit, and the entire suit could be run at once. Leading high can gain by saving a tempo when the appearance of dummy and partner's signal make it obvious that a shift is needed. The high lead will also avoid a potential disaster when dummy has Jxx and partner Q9x. It would be a shame to lead low, have partner play the nine, and declarer win the ten. Finally, leading high from AKxx shows partner where our honors are, giving him a clearer picture of the defensive assets.
Assuming that we lead the ace from AKxx, let’s look at how third hand should signal. Assume that upside attitude signals will be used. If dummy has Qxx(x) or Jxx(x), third hand's signal asks for partner to continue with a low card. However if dummy has any doubleton or three cards lacking the queen or jack, there is a choice about how the opening leader should continue when he receives an encouraging signal. Logically, an encouraging signal could either show the queen, or alternatively, it could show sufficient length that declarer's queen is doubleton.
I suggest that third hand's encouraging signal ask for the continuation of king and another card in the suit. This enables the defense to run the suit in the critical case when third hand has five cards, and it works well when the suit is 4-4 with declarer having a doubleton. If third hand has four (or five) to the queen, he is happy to have the opening leader continue with the king and another. It is only when third hand has specifically three to the queen that he would prefer opening leader to continue with a low card. In that case, third hand should normally discourage if it appears that he will gain the lead at some point. On the other hand, if dummy has three small and it appears likely that partner will have an entry, third hand should encourage.
Should dummy have a singleton or void in the suit led, the odds change. Declarer is rather unlikely to have a doubleton queen leaving the suit divided six-two. It figures to work better to have third hand's attitude signal show the queen, and to suggest that opening leader continue with a low card in the suit.
With the ace and king leads accounted for, it is time to move down the line. From KQx, KQTx, or KQ9x we do not want partner to unblock the jack or ace at trick one, so we cannot lead the king. Thus, we much select the queen, asking for an attitude signal. We would like for partner to encourage if he has the ace or jack and discourage otherwise.
From QJ9x we want partner to encourage when holding the ace, king, or ten; else discourage. If we adopt the queen as our standard lead from this holding, partner will discourage if he holds the ten and nothing higher. Futher, if declarer has the king, partner might have difficulty discerning whether we led from KQ or QJ. That's no good! Let's lead the jack instead, showing the queen and asking for an attitude signal with the ace, king, or ten. Hey! This looks like Rusniow.
The lead of the queen shows the king and asks for attitude with the ace or jack. The lead of the jack shows the queen (and possibly the ace or king) and asks for attitude with the ace, king, or ten. The ten shows the jack (and perhaps the ace or king) and asks for attitude with an honor. The nine shows the ten (and maybe the ace, king, or queen) and asks for an attitude signal. The eight or lower is either fourth best (if that's your agreement) or high from a weak holding that might include a higher spot card.
Be aware that the standard exceptions to Rusinow apply here. Lead the top of touching honors in partner's suit, dummy's suit, or (after you have preempted) in a suit you did not bid. Against notrump slams you should also lead the top of touching honors (The K lead is not ambiguous -- it always shows KQ! - AW) Additionally, if partner made any lead directing double (eg. 1NT P 3NT X), the suit you lead is assumed to be partner's suit, so your lead is standard. Logically, if you lead a doubleton, you are leading partner's suit, and so lead high to unblock.
Note: From KQJx it will usually be best to lead the jack, showing the queen and asking for an attitude signal with the ace or ten. If dummy holds two small (for example) and partner encourages, you can continue with a low card, running the suit when partner started with Axx and declarer T9xx, or setting up the suit cleanly when partner started with Txx and declarer A98x. If partner discourages on your lead of the jack, you will continue with the king, and partner will give present count.
In summary, Ace from AKx(x), AKTx, AKJx
King from KQT9x, AKJTx, AKQTx
Queen from KQx, KQ9x, KQTx
Jack from QJx, QJ8x, QJ9x, QJTx, KQJx, AQJx
Ten from JTx, JT8x, JT9x, KJTx, AJTx
Nine from T9x, T98x, QT9x, KT9x, AT9x
High from doubleton honors
Opening leader should be aware of when it is superior to lead low from three honors, when there is an appreciable chance that an opponent has four cards in the suit. In particular, Larry Edwards was famous for recommending leading low from five or six cards containing AT9, KT9, or QT9, but not the eight. He was right more often than not.
Thanks to Linda Lewis, who agreed to play "strong king leads" and then suffered through the ambiguous queen lead from KQ and QJ before she suggested Rusinow for the lead of the queen or lower.
Special thanks to my wonderful wife Kelly for being so supportive of all my bridge activities.