[arepo24]

Different people say different reasons. Some say lead the highest card, others say lead the lowest card.
Which is it?
Thanks

[DavidKok]

There are lots of different possible agreements about leading a suit. None of the agreements are strictly better than others, although of course theoretically there is a set of agreements that is best on average. Most important is to pick a set of agreements with your regular partner and stick with it. I think it is standard here in EU-land to lead second best from an empty suit that partner has bid, so you could default to that without prior discussion (although another thread suggests bottom of three small as the default).

[sfi]

I think I mentioned this in the other recent thread, but if you haven't supported the suit then you should simply lead your normal card. If you have shown 3+, then you have a choice. Either lead high to deny an honour or lead a spot card to help partner count the suit - you have to work out which information might be more important to partner.

What you shouldn't do is simply lead the highest card, particularly if it's an unsupported honour. There are a couple of major reasons for this:

• You can give up an unnecessary trick in the suit. Imagine you have Kxx, parther has AJTxx and declarer has the Qxx. Now declarer can set up a trick with the queen.
  
• You might save declarer a guess in the suit.
  
• You might remove an entry from your hand which would come in handy later in the defence.

So if you do lead high to show weakness, consider whether you can afford your highest card or should settle for your second highest and hope partner can work it out.

[Stephen Tu]

Could be high, low or neither. It's situational, and depends on agreements.

Doubletons: From honor-x, you pretty much have to lead high. This is for unblocking purposes, and also partner will know you have doubleton (or honor sequence).
From low doubleton, standard agreement is high, so partner can know when to give you ruff. But there are people who play Polish style 2nd/4th leads where they lead low from 2 small instead by agreement. This latter agreement is unusual and requires pre-alert in many jurisdictions, though I presume not in Poland.

Honor sequences: Lead high. e.g. K from KQx. This informs partner of holding the touching honor (if you raised), or holding doubleton, and lets you hold lead in case 2nd trick needs shift from your side. Also starts unblocking if necessary.

Interior sequences: high from the interior sequence, e.g. J from KJTx, T from QT9x (unless playing "0 or 2 higher" leads, which lead 2nd high from the interior sequence). This may help hold the lead and finesse against dummy's potential honor several times without having to get an entry back to your hand. It also preserves your tenace over declarer's potential honor if declarer has that card rather than dummy.

Holding the ace with the king vs suit: lead whatever your agreement is for AKx, lead the opposite with AK doubleton
Holding the ace without the king vs suit: lead the ace if you are going to lead the suit (weigh if alternatives might be better). Underleading aces vs suits is only for exceptional desperate situations, like you need a return ruff at trick 2 vs a slam.

3+ cds without honor: If you've raised promising length, usually high to deny honor. If you haven't raised, it depends on agreements. Some people play "third from even, low from odd", where you lead 3rd from 3/4/6, lowest from 5 (and 3 where it is both third and lowest). Others play "MUD" where you lead middle from 3 small. Polish 2nd/4th players also lead 2nd from 3. Fourth best players lead 4th from 4+ cds.

3+ cds with honor, but without sequence: Here you lead the spot card that conforms to your agreements. 3rd/low players would lead 3rd best from Kxx/Kxxx/Kxxxxx, low from 5 to an honor (and 3 to an honor). 4th best players would lead 4th best. This is the category that beginner players screw up by far the most and get taught bad info by their partners the most. A lot of them get some mistaken impression that it's normal to lead high, the honor from this holding. This is bad. The reason it's bad is the same reason why you as declarer generally don't bang down high card from hand, unless you have a solid sequence of honors. Like if you had Qxx vs AJxxx, you'd lead low to J, not lead the Q. This prevents a ten from being set up as a casher if say Kx was in the slot. Since you don't know whether you and partner combined have all the relevant touching honors/spot cards, you lead low to preserve a trick in some possible layouts. It might be necessary to keep an honor over declarer's potential honors/spots.

Exceptions: if you and partner have a huge fit in the suit, and suspect only 1 trick is likely to cash, you might lead high from some honor holding without a sequence, in an attempt to hold the lead in case a switch has to be made from your side at trick two. Or some other situations where you suspect need to hold the lead and have clues from the auction.

[arepo24]

Thanks to all.
I see that each situation is different and that there is no stock answer.
It is more of a partnership agreement.

[Zelandakh]

I like to play 1-3-5 in partner's suit even if the default is 2-4 in other suits. Typically the agreement is to lead the lowest from 3 support has not been shown during the auction, even if those 3 are 432, unless holding an honour sequence. If support has been shown then the highest can be led if that seems like it will be advantageous. From a doubleton the top one is always led (except AK). This scheme allows for a fast count to be obtained, which can be important in cash out situations.

[Douglas43]

It's not always right to lead partner's suit but it usually is (see this discussion about bots in a BBO forum https://www.bridgeba...tners-bid-suit/)
There is much to be said for leading on the same basis as you would in an unbid suit. It saves (both of you) trying to remember two different styles and takes away worries about whether partner has also remembered.

One aspect to consider is holdings that you would not usually lead from, like Axx or AQx. With these I would listen to the auction and consider factors such was is partner's bid an opening bid which might be a weak suit or an overcall which should have some lead directional intent. Then, unless the auction gave a strong reason to expect a void somewhere, I'd probably lead the Ace anyway and hope for the best...

[bluenikki]

arepo24, on 2020-October-23, 15:16, said:

Different people say different reasons. Some say lead the highest card, others say lead the lowest card.
Which is it?
Thanks

Is it a suit contract or not? The considerations are different.

For defending a suit with no important honors in partner's suit, the primary question is how many of partner's honors will cash. Therefore, any agreement that has you leading the same card from adjacent lengths is suicidal. Such as SAYC's leading second highest from both 4 and 5 small. Or leading highest from both xxx and xx. Or leading middle (second lowest) from xxx.

The same applies with an honor, with two exceptions (and these apply to notrump as well).

First, if you are on lead for the last time, it is probably right to agree to lead the honor, on the off chance it will hold.

Second, if the auction marks dummy as much stronger than declarer, so that any missing honors are likely on your left, it is right to agree to lead highest.

[undoubling]

If you have supported partner's suit w/ 3cds-----then you need to tell partner what to expect form you. With a "reasonable" honor (A,K, Q) 3rd---------lead LOW, otherwise lead the "top of nothing", telling your pard that your values lay elsewhere. The dummy will help your pard to decide WHERE your values "probably" are. Of course, with an honor sequence of your own, by leading ONE, then shifting to partner's suit, you can take ALL of the mystery out of your partner's return!!

[dsLawsd]

Mr. Tu has said a lot. What matters also is that you should project how the defense should go. Do you want a ruff later somewhere? Do you need to know whether to shift or continue/
If so, you might lead a King to decide that if partner holds the Ace.

Matchpoints or Imps? strategy shifts from max to insure a set sometimes.

Your signal toolkit may indicate a procedure. One interesting feature from Zia-Rosenberg is that they play regular signals for count and attitude at trick 1, Upside-Down for
the rest of the hand.

Naturally, this is why defense is the most difficult part of the game.

[miamijd]

The discussion so far has focused on what to lead in partner's suit against a suit contract. Stephen Tu's summary is excellent.

Since the OP didn't specify suit contract vs. NT contract, I will note that the only major differences are:

(A) you lead low from Axx(x), not the Ace, vs. NT contracts
(B) from 3 small, high is very bad; you can either lead middle or low depending on your agreement
© if you have KJx, consider leading the Jack. If you lead low, you may well block the suit.

Cheers,
Mike

[Huibertus]

Good post.

Just to add a couple of suggestions'{Lead high. e.g. K from KQx) I'd say Lead th K if you want partner to unblock i.e. KQTXX and lead the Q asking partner to encourage holding the J (or A or K).

[Holding the ace with the king vs suit: lead whatever your agreement is for AKx, lead the opposite with AK doubleton] I suggest to lead the A from an even number of cards, and the K from an odd number, asking partner to signal if an even or odd number of tricks can be cashed.

And an extra exception;

If you've agreed to lead low from Honor 3rd and you suspect the dummy holds the opps honors in the same suit, consider to lead high regardless, and the 2nd highest after retaining the lead. And of course the mirror of this... If you've agreed to lead high from Honor 3rd and you suspect the leader holds the opps honors in the same suit, consider to lead low regardless.

[arepo24]

bluenikki, on 2020-October-24, 07:33, said:

Is it a suit contract or not? The considerations are different.

For defending a suit with no important honors in partner's suit, the primary question is how many of partner's honors will cash. Therefore, any agreement that has you leading the same card from adjacent lengths is suicidal. Such as SAYC's leading second highest from both 4 and 5 small. Or leading highest from both xxx and xx. Or leading middle (second lowest) from xxx.

The same applies with an honor, with two exceptions (and these apply to notrump as well).

First, if you are on lead for the last time, it is probably right to agree to lead the honor, on the off chance it will hold.

Second, if the auction marks dummy as much stronger than declarer, so that any missing honors are likely on your left, it is right to agree to lead highest.

Yes, a suit contract - not NT.

[thepossum]

Hi all

I hope its ok to ask a point of clarification. Nobody has mentioned singletons which I always thought was an option against suits. Is there a reason?

Is it that you may be losing your only entry across to partner before having seen dummy etc

regards P

[Zelandakh]

thepossum, on 2020-October-27, 19:23, said:

Nobody has mentioned singletons which I always thought was an option against suits. Is there a reason?

That is because it is assumed that everyone knows which card to put on the table when leading a singleton.